CYC2025 - International Conference on Cyclotrons and their Applications (Chengdu)

27 Oct 2025, 09:00 → 31 Oct 2025, 15:00 Asia/Shanghai

InterContinental Chengdu Global Center

Tianjue Zhang (China Institute of Atomic Energy)

CYC2025 - International Conference on Cyclotrons and their Applications (Chengdu)

 

The International Conference on Cyclotrons and their Applications has a long history, dating back to the 1950s. The conference takes place every 3 years with the most recent events held in Beijing/China (2022, virtual meeting), Cape Town/South Africa (2019) and Zurich/Switzerland (2016).

 

The 24th international conference on cyclotrons and their applications (CYC2025) will take place in Chengdu, China on October 27-31, 2025. China Institute of Atomic Energy (CIAE) will host the conference. Professor Mingwu Fan, former director of CIAE and academician of Chinese Academy of Engineering, and Professor Hongyi Yang, director of CIAE, are invited to serve as honorary chairmen of the conference. The conference presentations will include invited talks, oral contributions and posters.

 

The 24th International Conference on Cyclotrons and Their Applications is supported by National Natural Science Foundation of China (Grant No.12542038).

CYC2025 Abstract Manual.pdf

CYC2025-banner.jpg

CYC2025 Conference Manual.pdf

CYC2025-poster.jpg

First Announcement of CYC2025.pdf

Second Announcement of CYC2025.pdf

Slides_online

• Monday Afternoon.zip
• Monday morning.zip
• Tuesday Afternoon.zip
• Tuesday Morning.zip

Monday 27 October

09:00 → 09:40 Conference Opening: Welcome Speech

09:40 → 10:10 Cyclotron and Technology (1): Session MOA-1

Convener: Dr Yu. Bylinskii (TRIUMF)

09:40 Perspective and design study of a high intensity heavy ion and proton compact superconducting cyclotron

Targeted α-therapy with α-particle-emitting isotopes such as 225Ac, 223Ra, 213Bi, 212Pb, has demonstrated a successful clinic trial effect. However, the major bottleneck for conducting translational research and future extensive clinical treatments is the limited availability of those α-emitting isotopes. Meanwhile, radioactive ion beam physics research, material irradiation and nuclear micro-porous membrane production demand high intensity heavy ion beams. A compact superconducting cyclotron for high intensity ion beam with a mass-to-charge ratio of 3 is being designed and developed by Institute of Modern Physics (IMP). The first such compact superconducting cyclotron is being designed which is dedicated to high intensity proton beam for 225Ac and 223Ra medical isotope production with extracted proton beam energy 120 MeV and proton beam intensity 0.5-1.0 mA by acceleration of H3+ beam through stripping extraction. The second one will be dedicated to high intensity heavy ion beams with a mass-to-charge ratio of 3 and extracted beam energy 120 MeV/A and typical beam intensity 5 pμA. Perspective and design studies of such high-intensity compact superconducting cyclotrons will be presented in the talk.

Speaker: Hongwei Zhao (Institute of Modern Physics, Chinese Academy of Sciences)

10:10 → 10:50 Take Group Photo & Coffee break

Taking Group Photo

10:50 → 12:00 Cyclotron and Technology (1): Session MOA-2

Convener: Dr Yu. Bylinskii (TRIUMF)

10:50 Status of the IsoDAR Project

I will present an overview of the current status of IsoDAR Cyclotron research and development, as well as the associated physics program.

Originally conceived to meet the requirements of the IsoDAR (Isotope Decay-At-Rest) neutrino experiment, the modular design of the HCHC (High-Current H₂⁺ Cyclotron) family enables the fabrication of cost-effective and compact cyclotrons covering an energy range from 1.5 MeV/amu up to 60 MeV/amu. These machines are expected to deliver a continuous-wave (cw) beam current of 10 mA, representing a tenfold increase over commercially available cyclotrons. This performance gain is enabled by accelerating H₂⁺ ions, injecting them through an RFQ embedded axially in the cyclotron yoke, and exploiting vortex motion, a collective beam-dynamics effect.

We have validated our design concepts through high-fidelity particle-in-cell (PIC) simulations, optimized the RFQ with machine-learning techniques, and are currently constructing the first 1.5 MeV/amu prototype. Beyond neutrino physics, the HCHC cyclotrons also hold significant potential for medical isotope production and fusion-relevant material testing.

Speaker: Andreas Adelmann (Paul Scherrer Institute)

11:20 Challenges for new Cyclotron Projects

ome of the new cyclotron projects currently under study or construction address new challenges. In particular, the START project of the company TRANSMUTEX to drive a subcritical reactor with a 4 MW proton beam, the 6 MW CYCIAE-2000 project, the IsoDar cyclotron of MIT, the new 230 MeV superconducting cyclotron for proton therapy and flash therapy in Dubna, and the upgrading of the Catania superconducting cyclotron to reach the 5-10 kW, along with their specific challenges, will be discussed. The procedure and tools to achieve high beam power, high reliability, setting optimization and automatic restart will be analyzed.

Speaker: Mr Luciano Calabretta (Istituto Nazionale di Fisica Nucleare, Laboratori Nazionali di Legnaro)

11:40 Frequency generation and multiple frequency synchronizations in accelerator systems

An accelerator system employing RF cavities requires the use of a stable RF source, and some require multiple frequencies, either for acceleration or for bunching. These frequencies must be synchronized in phase in order to work properly. These are usually derived from a single low phase noise master reference frequency source. A fixed frequency oscillator or a variable frequency oscillator such as a frequency synthesizer are commonly used as the master frequency oscillator. Other frequencies are generated using this master source either through frequency multipliers or phase-locked loops. Phase noise is a crucial performance index of these sources, because once generated, phase noise will be persistant and cannot be corrected. Other active devices such as RF amplifiers, frequency up/down converters will contribute to the additive phase noise. The various aspects including merits and limitations of a master source, frequency multipliers and PLLs, together with the effect on beam quality on different types of resonant cavities, are investigated.

Speaker: Ken Fong (TRIUMF)

12:00 → 13:30 Buffet Lunch

Buffet Lunch

13:30 → 15:00 Cyclotron and Technology (1): Session MOB

13:30 New Injection for TRIUMF 500 MeV Cyclotron

A new injection beamline for the 500 MeV cyclotron has been designed, constructed, and commissioned. Approximately 40 meters of electrostatic transport now replace the previous injection system, extending from the H⁻ ion source to the vertical injection section. The upgrade also includes the integration of a second H⁻ ion source, connected through additional electrostatic beam transport, to provide operational flexibility and redundancy.
A novel suppression scheme for stray magnetic fields from the cyclotron has been implemented using a continuous, in-vacuum passive µ-metal shield along full beam transport. Beam bunching is performed with a new three-harmonic buncher, whose amplitude has been calibrated through beam-based techniques. Additional diagnostics were introduced to enable non-interceptive monitoring of beam position.
The injection system operates under ultra-high vacuum (low 10⁻⁸ Torr), achieved using stainless steel and ceramics materials and all-metal seals.
During commissioning, new high-level software applications for online tuning were deployed. These tools are now integrated into routine operation, providing enhanced automation and reproducibility of tuning procedures. Overall, the new injection system significantly improves the robustness, flexibility, and performance of cyclotron operations.

Speaker: Dr Yu. Bylinskii (TRIUMF)

14:00 Upgrade of the INFN-LNS Superconducting Cyclotron: towards its Reassembling and Commissioning

The upgrade of the Superconducting Cyclotron at INFN Laboratori Nazionali del Sud in Catania is aimed at improving its performance in terms of intensity of light ions, as well as in terms of reliability. The project was financed in 2019 by the Italian Ministery of University and Research. The Cyclotron was kept operative until the end of 2020, then in 2021 it was dismantled, so as to proceed with the upgrade.
To get the expected improved performance as a result of the upgrade, a new extraction system will be installed to allow for extraction by stripping. The main components to be replaced are the superconducting magnet, the liners, the dee cones, the trim coils power supplies.
The status of all the components of the Cyclotron is here described with particular emphasis on the design, construction and tests of the new superconducting magnet, which is the main and most challenging device in this upgrade operation.

Speaker: Dr Danilo Rifuggiato (Istituto Nazionale di Fisica Nucleare)

14:20 Recent Upgrade of RCNP AVF Cyclotron

The upgrade project of the RCNP K140 AVF cyclotron was initiated in 2019 to provide intense light-ion beams for the production of short-lived radioisotopes and high-quality, high-intensity beams for precision nuclear physics experiments. Except for the main coil, pole pieces, and yoke of the cyclotron magnet, most components were replaced with newly fabricated systems. In particular, the radio-frequency, injection, and extraction systems were redesigned to accommodate higher beam currents.
A new coaxial-type resonator was developed to cover 16–36 MHz, enabling the acceleration of standard ion species under harmonic modes of h = 2, 3, 6. The ion source acceleration voltage increased from 15 kV to 50 kV to enhance beam intensity and reduce emittance, improving injection efficiency. The central region was reconfigured to optimize beam transmission from the LEBT system.
Beam commissioning commenced in 2022. A 28.5 MeV helium beam was successfully accelerated and is used to produce At-211 for targeted alpha-particle therapy. Light-ion beams have also been injected into the K400 ring cyclotron and extracted for nuclear structure studies. A 392 MeV proton beam is used to generate white neutron and muon beams.
In 2024, heavy-ion acceleration resumed, and a variety of ion beams became available for research and applications. Efforts have also been made to improve operational stability and reliability.

Speaker: Tetsuhiko Yorita (Osaka University)

14:40 Operation and Upgrades of Beam Diagnostics for Cyclotron Accelerators at HIRFL in Lanzhou

Although the cyclotron accelerators at HIRFL, namely the Sector-Focused Cyclotron (SFC) and the Separated Sector Cyclotron (SSC), are over sixty years old, beam commissioning continues to run successfully. The SFC, installed in 1962, can accelerate heavy ions to 17 MeV per nucleon or protons to 37 MeV, with an average current of 10 µA. The SSC (Sector-Separated Cyclotron), commissioned in 1975, serves as our primary accelerator. It is capable of accelerating ions to energies of up to 100 MeV per nucleon or protons to 110 MeV.We will present advancements in beam diagnostics designed to enhance machine operation efficiency and convenience, as well as to enable more precise and comprehensive measurements of beam parameters. The primary focus includes the development of key sensors and electronics tailored to meet the requirements for low-intensity current and transverse emittance measurements. Additionally, it presents the design and implementation of a beam diagnostics control system based on a cloud architecture, operating on a highly reliable server cluster. Native device control and data processing software run within virtual computers on the cloud platform, enabling comprehensive beam measurements including beam current, position, transverse profile, emittance, energy, and longitudinal bunch length. The system apples the EPICS communication protocol and features an integrated user control interface.

Speaker: Yong Zhang (Institute of Modern Physics, Chinese Academy of Sciences)

15:00 → 15:20 Coffee break

15:20 → 16:30 Cyclotron and Technology (1): Session MOC

15:20 The Low-temperature and High-temperature Superconducting Cyclotrons Developed by CIAE in the Last Ten Years

The cyclotron, which has been around for over 80 years, experienced a period of vigorous development in the last ten years due to urgent needs in multiple application fields, specially for ultra-compact, ultra-lightweight, and high-power cyclotrons.
Since 2013, a low-temperature 230MeV superconducting cyclotron CYCIAE-230 has been developed and successfully obtained the first beam at 231MeV in 2020, which is the first SC cyclotron in China. Currently, CYCIAE-230 has commenced industrialization in Chengdu, China, for proton therapy of cancer and proton irradiation of aerospace chips. Since 2019, a 100MeV high-temperature SC cyclotron CYCIAE-100B has been designed and is under construction now, which is the first try for iron-less, ultra-lightweight cyclotron development. In addition, CIAE started recently an ultra-compact, multi-particle (charge-to-mass ratio of 1:2) SC cyclotron project CYCIAE-36A, for accelerating α and H2+ beam. It will be used for production of 211At, the study of the effects of α irradiation on new materials and aerospace biological effects, and the large-scale production and stable supply of commonly used PET isotopes. Finally, we have been continuously optimizing the design of a 2GeV high-power, high-energy efficiency isochronous FFA proton accelerator CYCIAE-2000, and have been conducting necessary key technical research and engineering design verification, including the 1:4 FDF magnet based on high-temperature superconducting technology.

Speaker: Tianjue Zhang (China Institute of Atomic Energy)

15:50 Design of the EcoCyclone Permanent Magnet Medical Cyclotron

We present the magnet design of an adjustable-field isochronous permanent magnet cyclotron concept, capable of accelerating protons to 18 MeV. Within the cyclotron, the permanent magnet is distributed about the cyclotron return yoke above and below the midplane in rotatable cones. With an outer radius of 1.36 m and height of 1.22 m, the design can replicate the field strength (up to 2.3 T peak) and pole gap of the IBA Cyclone(R) Kiube. We consider efficient application of permanent magnet material, and report the resulting, simulated magnetic field, RF frequency, rough estimate of total power and other properties of the machine. For use as a radio-pharmaceutical cyclotron, we find an 18F production target would cause much less activation in neodymium permanent magnets than in samarium-cobalt permanent magnets, resulting in a strong preference for using the former in such a cyclotron. The torque required to turn the permanent magnet cones to adjust the field is found to be below 2800 Nm, and no demagnetisation due to applied magnetic field is expected for the case of neodymium magnets.

Speaker: Alexander Herrod (Ion Beam Applications (Belgium))

16:10 Enhanced Ion Beam Delivery Through AECR-U Upgrades at UMCG-PARTREC

A series of upgrades were implemented at the AECR ion source at UMCG-PARTREC to improve ion beam performance. The focus was on increasing beam intensity, enhancing long-term stability, optimizing ion species control in cocktail beams, and identifying optimal RF injection frequencies for plasma heating. A key enhancement was the installation of an Einzel lens. This increased the transmission efficiency through the analyzing magnet from 50% to 76% for 23 kV helium beams. As part of the EUROLABS ERIBS collaboration, a novel ion beam monitoring system was developed. It visualizes and records beam intensity and stability in real time. The system uses a semi-automated feedback loop that exploits defects in ion-optical imaging to parasitically monitor the analyzed beam. The gas mixing system was upgraded with a third gas valve and improved control mechanisms. This allows precise and rapid tuning of the ion fraction in xenon-krypton-oxygen cocktail beams. A frequency scanning device was introduced to evaluate beam performance across RF injection frequencies from 12.75 to 14.2 GHz. It successfully identified regions of high intensity and stability. Together, these upgrades enable more reliable and tunable ion beam delivery for experimental applications.

Speaker: Herman Kremers (Particle Therapy Research Center)

16:30 → 18:30 Monday Poster Session: MOP

16:30 Optimization of Isochronous Magnetic Fields and Beam-Dynamics Simulations for a High-Intensity Superconducting H3+ Cyclotron

High-intensity proton cyclotrons have widespread applications in scientific research, medical treatments, and industrial processes. As cyclotron technology continues to evolve, the trend leans toward more compact designs with increased beam intensity. Our proposed design involves a 120 MeV/u superconducting H3+ cyclotron named SK1000, capable of achieving 3 times the operational beam intensity through foil stripping. This configuration meets the demand for compact and high-intensity cyclotrons in practical applications. However, the intense space charge effects have significant impact on proton beams during injection, acceleration, and extraction, imposing stricter requirements on magnet design, RF systems, and beam extraction system. Particularly in the magnetic system, we aim to achieve a magnetic field with high precision(±10Gs), strong focusing capability, and excellent isochronism(±0.3‰), while simultaneously meeting the stringent requirement for a large axial acceptance in the central region, as well as realizing a single-turn extraction orbit using a stripping foil. Throughout the design and optimization of the magnetic system, continuous efforts are devoted to exploring and implementing effective methods for enhancing magnetic field performance and efficiency. And We simulated the baseline model of SK1000 by OPAL during acceleration and extraction.

Speaker: Guoliang Dou (Institute of Modern Physics, Chinese Academy of Sciences)

16:50 Research on design of neutron beamlines based on the 50 MeV proton cyclotron

With the growing demand for neutrons in applications such as detector calibration, device irradiation, and cross-section measurements, neutron sources are advancing toward higher energy and higher flux. In Beijing, China, two neutron beamlines, a quasi-monoenergetic one and a white light one, based on a proton cyclotron with a maximum energy of 50 MeV is under construction and preparation. We designed a quasi-monoenergetic neutron beamline, focusing on the target chamber and collimator. Lithium was selected over beryllium as the target material due to its superior quasi-monoenergetic peak performance. Parametric studies on lithium thickness revealed its impact on the neutron peak characteristics. Energy loss of protons through titanium films and argon gas was evaluated to guide chamber design. Neutron spectra and fluxes were simulated at various positions, leading to an optimal collimator length of 2 m based on flux and peak ratio. Regarding the white light beamline, detailed simulations and discussions were conducted on the composition of the shielding and collimation structure, leading to the determination of the final design. This approach significantly reduced the amount of cast iron required, resulting in a notable decrease in overall weight. These above-mentioned works provide key data for the beamline's construction and operation.

Speaker: Xiaobo Li (China Institute of Atomic Energy)

17:10 Research on the Production of Ge-68 through Cyclotron Proton Irradiation of Alloy Solid Targets and Encapsulated Targets

This study compares the production of $^{68}\text{Ge}$ using proton irradiation on two types of targets: an electroplated gallium-nickel alloy solid target and a niobium-encapsulated capsule with natural gallium. The alloy target was prepared on copper via electroplating, while the capsule was designed and fabricated to be irradiated in a cyclotron. The generated $^{68}\text{Ge}$ was then separated and purified using resin columns. Results show the electroplated target had a smooth surface and good adhesion, but its low loading capacity and vulnerability to thermal damage limit its use for large-scale production. The niobium-encapsulated target, with its higher loading capacity, improved stability and safety under irradiation, though it requires precise welding and sealing due to gallium's low melting point. For the separation and purification of $^{68}\text{Ge}$, the dissolution of the electroplated target is an open operation that introduces significant impurities, necessitating a combined purification process using both chelating and gel resins. In contrast, the niobium-encapsulated target allows for a closed operation, resulting in lower impurity levels and offering distinct advantages for subsequent purification.

Speaker: Yong Li (China Institute of Atomic Energy, Tsinghua University)

17:30 Cooling optimization design of ultra-compact 9.5MeV cyclotron—18F liquid targets

For the treatment of major diseases such as cancer, Positron Emission Tomography(PET) nuclear medicine imaging technology has irreplaceable advantages over traditional imaging technology.At present, 18F-2-deoxyglucose (18F-FDG) is a widely used positron electron drug in clinical practice in China. Therefore, the Chinese Academy of Atomic Energy has carried out the research and development of the "ultra-compact 9.5MeV cyclotron — 18F liquid target" for medical PET isotope production. By using a 60A proton beam obtained by a 9.5MeV cyclotron, a liquid target filled with oxygen-rich water is bombarded to produce 18F on the order of 1.5 Curie (Ci). The 30 titanium window is used as the vacuum membrane window, and the 25 Havar membrane window is used to seal the liquid target cavity. The purpose of this paper is to reduce the damage of the beam to the titanium window and the Havar membrane window, and the helium cooling chamber innovatively adopts a cyclic helium cooling design to reduce the temperature on the membrane window. Simulating the cyclic helium cooling process through finite source software, the flow rate of helium is introduced with a flow rate of 2.5m/s. So, the feasibility of the cooling design for reducing the temperature of the membrane window is analyzed and verified.

Speaker: Ms Xue Ran (China Institute of Atomic Energy)

17:30 Jacobian for the Design of Variable-Gap Dipole Magnets

When exploring the design of constant-tune (isochronous) cyclotron magnets, we found it useful to employ dipole magnets with a variable gap height, allowing fine control of the radial field profile. To determine the optimal gap-shape profile that produces a prescribed magnetic field distribution, we employ an iterative search using 3D finite-element simulations (e.g., OPERA). To minimize the number of iterations, we use a Newton–Raphson scheme, which requires knowledge of the Jacobian matrix relating field errors to gap corrections. In this work, we derive exact analytical expressions for this Jacobian in two limiting cases: the non-saturated regime, obtained using conformal mapping, and the fully saturated regime, modeled with current sheets. We then describe a method to interpolate between these two limits to obtain a general Jacobian valid across the full range of magnetization. This approach serves as a practical building block for designing variable-gap magnets with only a few iterations; it can also readily be applied to the design of fixed-field alternating-gradient (FFA) magnets.

Speaker: lige zhang (TRIUMF)

17:30 Research on Separation Technology for the Production of Ga-68 by Cyclotron

This study describes the production of $^{68}\text{Ga}$ by irradiating an enriched $^{68}\text{ZnCl}_2$ liquid target with a 12 MeV, 50 μA proton beam in a cyclotron. The post-irradiation products were first simulated, and a simulated solution was prepared based on the computational results.

This solution was adjusted to approximately pH 5.0 and subsequently loaded onto a pre-conditioned ZR resin. The subsequent purification involved a two-step process on the ZR resin: first, washing with HCl (pH = 4) effectively removed 99.99% of the ⁶⁸Zn substrate; second, ⁶⁸Ga was efficiently eluted using 5 mol/L HCl.

The resulting $^{68}\text{Ga}$-containing eluate was then loaded onto a pre-conditioned anion exchange resin for further purification. Residual impurity ions were removed by washing the resin with 5 mol/L HCl, followed by the elution of purified $^{68}\text{Ga}$ using ultrapure water. The chemical purity of the final $^{68}\text{Ga}$ sample was confirmed to comply with the quality specifications for accelerator-produced $^{68}\text{Ga}$ as defined in the European Pharmacopoeia.

Speaker: Pengfei Zhao (China Institute of Atomic Energy)

17:30 Simulation and experimental study on the production of actinium-225 radionuclide based on a 100MeV cyclotron

Actinium-225 is a radionuclide of significant interest in the field of Targeted Alpha Particle Radiotherapy (TAT), with its targeted drugs showing promising applications for prostate cancer, brain tumours, neuroendocrine tumours, and more. One of the primary approaches being explored by major international laboratories for the commercial production of $^{225}\text{Ac}$ involves the spallation reaction induced by high-energy proton accelerators (>70 MeV) irradiating a $^{232}\text{Th}$ target. This study conducted detailed simulations using the Monte Carlo program FLUKA to analyze the production yield of $^{225}\text{Ac}$, reaction products, variations in impurity radionuclide yields with cooling time, and the $^{227}\text{Ac}$/$^{225}\text{Ac}$ ratio at different energies in the context of irradiating a thorium target with the 100 MeV proton cyclotron at the China institute of atomic energy(CIAE) in China. The findings provide a reference for subsequent engineering experiments on producing $^{225}\text{Ac}$ via irradiation of thorium targets with medium and high-energy proton accelerators.CIAE conducted irradiation experiments on metallic thorium targets using the 100 MeV cyclotron, achieving an experimental production yield of 0.02 mCi/μAh.

Speaker: Yunlong Zhao (China Institute of Atomic Energy)

17:30 Stability Improvement of Genetic Algorithm and Study of Surrogate Model for CSNS-FFAG Lattice Optimization

In accelerator physics, lattice optimization is a foundational step for subsequent work. Traditional optimization methods face problems that balancing several input parameters with conflicting optimization objectives and the prohibitive computational cost of key physics simulations, particularly for Dynamic Aperture (DA). As a part of the China Spallation Neutron Source (CSNS) FFAG project, this study aims to enhance the efficiency and reliability of its multi-objective lattice optimization workflow.
This study focuses on improvements to two critical components of this process. First, we refine the elite clustering process to increase the stability of the genetic algorithm (GA), leading to more robust optimization results. Second, for the time-consuming physics simulations, we have verified the unique suitability of a Transformer-architecture surrogate model for this application. Compared to conventional neural networks, its prediction accuracy is higher.
The combination of the stability-improved genetic algorithm and the high-precision Transformer surrogate model provides a fast set of optimization tools for lattice. It can provide guidance for the choose of lattice parameters in FFAG and significantly accelerate the design and optimization time for the actual engineering project.

Speaker: Yan Cui (Institute of High Energy Physics)

18:10 A NEW HIGH CURRENT POWER SUPPLY FOR THE MAIN CYCLOTRON MAGNET AT NHS

This study presents the design and development of a new power supply intended to provide a highly stabilized current, serving as a replace-ment for an existing linear converter used in the main magnet of the NHS cyclotron. The power supply is capable of operating in DC mode with currents reaching up to 900 A. It employs a proven modular design approach, previously implemented in other cyclotron facilities, featur-ing a 12-pulse input rectifier and a single DC link that powers a DC/DC chopper module. This paper outlines the design phases and simulations conducted, along with a comparison to field tests performed since its installation in the third quar-ter of 2024.

Speaker: Dr Miguel Pretelli (OCEM Energy Technology)

18:10 A powder target preparation technology for producing the 44Sc radionuclide

1. Introduction
   44Sc is a novel radionuclide with a high branching ratio (Eβ+av=632 KeV, I = 94.3%), which is highly suitable for positron emission tomography (PET) imaging, endowing it with broad application prospects in the field of nuclear medicine.
   The preparation of 44Sc by 44Ca (p, n) 44Sc nuclear reaction in a cyclotron is the most widely used preparation method. In this study, calcium oxide powder was used as the target material and the pressing experiments were carried out.

2. Material and Methods
   The influence of different pressures and different target material quantities on target sheet formation was investigated. A certain amount of calcium oxide was weighed, and pressing experiments were conducted under different pressure conditions to observe the formation of the target sheet.

3. Results and Conclusion
   The results of different pressure and target material quantities are shown in Table 1. When the pressure reaches 49 KN and the amount of target material reaches 250 mg, target sheets that meet the requirements can be obtained. Simulation calculations of the target pieces were carried out, and the results are shown in Figure 1. The maximum surface temperature of the target piece is 615℃, which can meet the production requirements of 44Sc.

Speaker: haomiao chu (High-Tech Atomic Co., Ltd.)

18:10 Advances in Simulation Tools and Cyclotron Projects at Lanzhou University

This paper summarizes recent progress in cyclotron research and development at Lanzhou University. In computational physics, a comprehensive time-domain beam dynamics code, RAYS, has been developed that solves the Newton-Lorentz equation using 4th or 5th order Runge-Kutta integrators to simulate particles from injection to extraction. RAYS supports synchrocyclotron modeling with a time-varying RF frequency module and facilitates automated design workflows via both GUI and console modes. Additionally, a high-stability closed-orbit analysis program RSCYC has been created. It employs a multi-scale coarse scanning method combined with the Adam optimization algorithm and symmetry constraints to ensure rapid, stable convergence to physical solutions. The numerical accuracy of these codes has been validated through cross-verification with mainstream programs.
Leveraging these in-house dynamics programs, several cyclotron projects are under development. For hadron therapy, the 230 MeV superconducting isochronous cyclotron (SC230) has entered the full production phase, with some systems already mechanically fabricated. Meanwhile, the comprehensive physics design and dynamics analysis for the 210 MeV superconducting synchrocyclotron (S2C210) have been completed. For isotope production, the 8 MeV proton cyclotron (Smart8) is also in full production, while the physics design for the 30 MeV alpha cyclotron (Smart30α) has been finalized.

Speaker: Yongquan Wang (Lanzhou University)

18:10 Alternative method and practice to evaluate cyclotron RF control performance during commissioning

Low-level radio frequency (LLRF) systems play an essential role in cyclotron control, and the beam quality is closely tied to the overall performance of the RF system. Efforts have been carried out by the individuals of the China Institute of Atomic Energy (CIAE), focusing on the design of a self-excited digital LLRF system for ultra-lightweight high-temperature superconducting cyclotrons in special environment applications. In CIAE, a self-excited digital LLRF controller has recently been developed and tested for the cyclotron RF control. In practice, for this special cyclotron, however, it is uneconomical to construct a dedicated vacuum tank just for the hot test of the RF system. Since the Q value and thermal drift of the cavity can be made identical under atmospheric or vacuum conditions, an alternative testing method has been developed to evaluate the performance of the LLRF control system, along with the cavity and the high-power RF amplifier. The cavity is excited by a 20kW solid-state power amplifier using a directional coupler, with a Q value of 2500, at a frequency of 77 MHz. Two dedicated digital signal processors, together with the ADCs, are included in the reported LLRF to achieve amplitude-phase control. Communication between DSPs is achieved through dual-port SRAM. A fast PID algorithm for IQ modulation was designed, achieving a group delay of less than 800 ns. This paper reviews the design of the self-excited digital LLRF, along with preliminary test results.

Speaker: Zeyuan Xia (China Institute of Atomic Energy, Chengdu Cyclotron Science and Technology Co., LTD)

18:10 An 85MHz-133.5MHz broadband radio frequency power source for synchrocyclotrons

In the operation system of a synchronous cyclotron, a broadband high-power RF power source plays an extremely important role. The RF power source is responsible for generating and providing high-frequency alternating electric fields, continuously injecting energy for particle acceleration. Its performance directly determines the acceleration efficiency, beam quality, and operational stability of the accelerator. This article introduces a broadband RF power amplifier with a frequency range of 85-133.5MHz. It has a 15kW RF power output capability and good in band flatness. It has complete functions for incident and reverse power detection, as well as standing wave ratio protection, over reflection protection, and over excitation protection. The human-machine interface is friendly, making it a mature power amplifier

Speaker: Yusong Chen (SPlC Nuelectronic Company Limited)

18:10 Applications of AI/ML in Virtual Cyclotron Prototyping: Challenges and Opportunities

Cyclotron design involves extensive computations for both individual accelerator systems and particle dynamics, requiring careful optimization of numerous interdependent parameters. The integration of artificial intelligence (AI) and machine learning (ML) into cyclotron design and operation is already demonstrating significant benefits, accelerating development, enhancing control, and improving system reliability. AI-driven approaches have the potential to revolutionize cyclotron optimization, enabling researchers to streamline design processes, explore a broader parameter space, and ultimately enhance device performance. This presentation discusses initial results from applying ML to magnetic field shaping and analyzes the broader opportunities and challenges in leveraging AI/ML for virtual cyclotron prototyping. The use of AI in the development of software for beam dynamics, particularly for seamless integration between 3D models, electromagnetic field simulation programs, and particle tracking, has significantly simplified the process and taken it to a new level.

Speaker: Oleg Karamyshev (Joint Institute for Nuclear Research)

18:10 Artificial isochronous magnetic field maps

A software tool has been designed which allows us to make isochronous cyclotron field maps. The rotational symmetry number, the center field, the particle properties, the maximum radius and the sector spiraling angle as function of radius can be freely chosen. Out of four radius-dependent parameters (flutter, hill-field, valley-field and sector azimuthal extent), the user can define two of them freely and the tool will then calculate the complementary two; from that the full isochronous map is calculated. The azimuthal field profiles are defined by the hill field and the valley field which are connected by user defined transition zones. These zones may have a double-quadratic or cubic form factor. For the average isochronous field, a precise theoretical formula is used. The tool, in combination with a closed orbit code, may be used for exploring the parameter space of new cyclotrons to be designed. This may predict optical properties such as tunes and structural resonances. The author designed the tool in order to validate a theoretical model that predicts the energy limit of isochronous cyclotrons (as presented in the previous cyclotron conference). Equations are derived and the fundamentals of the tool are explained. Good precision of isochronism is confirmed by closed-orbit integrations for a wide range of the field map parameters introduced above.

Speaker: Willem Kleeven (Ion Beam Applications (Belgium))

18:10 Beam dynamics modeling in the superconducting cyclotron MSC-230

The dynamics of a proton beam in the MSC230 cyclotron were simulated. Since the maximum beam current is limited by extraction efficiency, an approach was employed, in which the beam trajectory started at the deflector with an emittance equal to its acceptance and ended at the entrance of the ion source. This method allows for a detailed characterization of the phase space boundaries for the beam originating from the cyclotron’s central region. In the particle tracking simulations, the results of computer modeling of the accelerating and magnetic systems were used, obtained from 3D electromagnetic field maps in CST Studio Suite.

Speaker: Dr Galina Karamysheva (Joint Institute for Nuclear Research)

18:10 Collimator design in the injection line of the ARRONAX C70XP cyclotron

A low energy collimator is being designed for the injection line of the C70XP cyclotron at Arronax. The context of its conception follows the studies that were performed with an Allison emittance-meter and several simple collimators*. The studies show the presence of offset beams, beamlets and hollow beams inside the injection line. The new dedicated collimator, based on four independent and adjustable slits, is planned to allow selection of the transverse geometry of the beam.
The design of the collimator is constrained by a number of considerations, including spatial limitations, beam power, electronic perturbation, and radiation. These considerations are taken into account to ensure that the collimator does not cause any disruption to other nearby systems.
The primary objective of the collimator is to be robust and to allow for electric measurements. The collimator will be used to conduct a study on the potential optimisation of the transmission from the injection line to the target, as well as the beam shape. In order to achieve these objectives, it is imperative that the collimator performs precise displacement and precise electrical measurements. The motor control and electrical measurement functions will be integrated into the EPICS environment. The paper presents the advancement of the project and also the initial results of the bench prototype control system.

Speaker: Teddy Durand (GIP Arronax)

18:10 Compact Beam Energy Monitor for Cyclotrons

Determining the energy of cyclotron beams is challenging. Calculating it from the machine settings typically results in an error of several percent. Higher accuracy requires measurement, but each developed measurement system has disadvantages: either the space requirement is large, the unit is destructive, or the signal evaluation is complicated. The Beam Energy Monitor (BEM) was designed to provide an ideal solution: compact size, non-destructive sensors, low energy consumption and user-friendly operation. This was achieved by developing an innovative sensor unit*, which enables accurate time-of-flight measurements on an extremely short flight path. The unit's signal is acquired and processed digitally. Various digital signal processing methods were evaluated using simulated probe signals to determine the most effective method of measuring time difference between pulses. The signal processing was tested using pulses from a generator. The results show that time measurements with an absolute error of less than 1 ps were achieved. The accuracy of the complete system during practical operation was also investigated. Neutron threshold reactions showed that the measurement accuracy is at least one order of magnitude better than the calculated energy value accuracy. The prototype unit was developed for the cyclotron at the HUN-REN Institute for Nuclear Research. Installed in the main beamline, it can monitor the beam energy continuously and independently from the beamline in use.

Speaker: Zoltán Kormány (HUN-REN Institute for Nuclear Research)

18:10 Conceptual Design of Central Region of PSC250 Superconducting Synchrocyclotron

PSC250 is a superconducting synchrocyclotron used for producting 250MeV protons for cancer therapy. It's the first superconducting synchrocyclotron developped by CIM (Hefei CAS Ion Medical and Technical Devices Co., Ltd.) for its advantages in small size and low cost. A new program named CIMSC has been developped especially for beam dynamics calculation in synchrocyclotrons from ion source to extraction region. Some detailed results have been introduced in this article, such as the central region electrodes configuration with a closed ion source, the ratios of captured and lost protons, good centerring of protons, the profiles of RF frequencies vs time and magnetic field vs radius, and so on. Optimal central region for protons with the largest capture ratio and good centering has been designed which will be shown in below text.

Speaker: 静霞 公 (Institute of Plasma Physics)

18:10 Design and commissioning of a 10 MeV cyclotron accelerator cooling system

The proposed cooling system is designed with a high reliability factor and considering the economic issues and costs based on the use of a 40 ton chiller for temperature changes of 4.5 to 10 degrees Celsius, which is able to continuously control the water temperature in this range.
In this system, the parts of magnet coil, cavity, power transmission line, ion spring and radiofrequency current amplifier with an inlet water flow of 201.9 L/min are fed from an air-cooled chiller at a height of 40 m on the roof of the building along with a vertical industrial water pump of 4 KW and has been done in CST software.
we showed the distribution of surface flow on the cavity and determined the hottest point of the cavity and used Solid Works software to geometrically model it. The magnet system was made up of hollow layer coils with a square outer cross-sectional area to the side of 10 mm and an inner cross-sectional area of a circle with a diameter of 5.7 mm, and for the power transmission line due to a change in the drampedance of 50 ohm when the temperature increased, the cooling system was used.In the PIG ion spring with a power consumption of 500 watt and The amplifier part of the water pressure limit lamp is set at 3.5 bar pressure for optimal cooling.
In this study, practical solutions are presented in the optimal design and commissioning of the cyclotron accelerator cooling system.

Speakers: Mohammad Yousefi Moghadam (Amirkabir University of Technology), Hossein Afarideh (Amirkabir University of Technology)

18:10 Design and optimization of scanning magnets for BNCT facility

Boron Neutron Capture Therapy (BNCT) is a cell-level precision targeted treatment modality. This paper designs a scanning magnet system for an 18 MeV/1 mA proton cyclotron-based BNCT facility. By continuously scanning in both horizontal and vertical directions using two scanning magnets, the system delivers a flat-topped square beam density distribution of 100 mm × 100 mm with uniformity exceeding 90% on the target, thereby preventing thermal overload on the target. Additionally, the scanning magnets operate at a maximum frequency of 200 Hz, inducing significant eddy current effects. The paper first introduces the layout of the scanning magnet system. Subsequently, the study compares the electromagnetic characteristics and eddy current effects of silicon steel and ferrite yokes, analyzing the temperature rise in the magnetic yokes caused by eddy current losses. Particle tracking was employed to validate the effective deflection of the beam, while the designed scanning waveforms verified the uniformity of the beam density distribution.

Speaker: 一平 刘 (Huazhong University of Science and Technology)

18:10 Design and Optimization of the Central Region of a Compact Superconducting Cyclotron

The intensity and quality of the extracted beam are critically influenced by the central region structure. Variations in the central region design can lead to difference in beam transmission efficiency, largely attributable to divergent acceleration dynamics during the initial few turns. In cyclotrons employing internal ion sources, the very low beam energy at the source outlet makes the beam highly sensitive to changes in the central region design. Therefore, optimizing the central region is necessary to ensure high transmission efficiency and better beam quality. This study presents a conceptual design simulation for the central region of a compact superconducting cyclotron designed for radioisotope production. Beam trajectory and centering are optimized through adjusments of the ion source position, the dircetion of the opening slit, and puller electrode geometry.

Speaker: panpan zheng (ShanghaiTech University)

18:10 Design of a large spot and high uniformity beam line

The 50 MeV medium-energy proton cyclotron device developed by China Institute of Atomic Energy provides important test conditions for space radiation environment simulation, space radiation protection design and application research. This accelerator fills the gap of proton and neutron irradiation test conditions in the energy range of 30 MeV to 50 MeV in China.
To provide a large-area and high-uniformity proton beam spot of 300 x 300 mm for irradiation tests, it is necessary to perform beam homogenization treatment to meet the requirements of irradiation area and uniformity simultaneously. To achieve both large beam spot and high uniformity, this paper compares schemes such as scanning magnets, beam expansion and scattering, and nonlinear high-order magnets. The design and beam dynamics simulation of the proton target station transmission system in the simulation experimental device are carried out. Through multiple beam transmission simulations with random errors, the uniformity of the beam reaches 90% under the condition of obtaining a 300 x 300 mm large beam spot. Finally, the scanning magnet scheme is selected as the most suitable beam homogenization scheme for this simulation device,and the overall design results of the beam transmission system are presented.

Speaker: Jing Hu (China Institute of Atomic Energy)

18:10 Design of Magnetic Field Measurement Device and Research on Magnetic Field Shimming for 50MeV Proton Cyclotron

In order to achieve the magnetic field measurement work for the 50MeV proton cyclotron irradiation device, a fully automatic magnetic field measurement device based on the Hall effect method is designed, using non-magnetic materials G10 and PEEK with high strength and wear resistance, optimizing the gear ratio, reducing the weight of the device, and adjusting the magnetic field measurement process to shorten the measurement cycle. The installation accuracy of the magnetic field measurement device reaches ±0.03mm, and the installation accuracy of the shims after adjustment is as high as ±0.02mm. By using a specific shim positioning tool, the shim adjustment accuracy reaches ±0.02mm. Ultimately, through the use of this new magnetic field measurement device, five magnetic field measurements and four high-precision shimming operations have been carried out, successfully completing the magnetic field measurement work of the 50MeV proton cyclotron and achieving good results. The isochronism goal of integral slip phase not exceeding ±10° was achieved, meeting the physical design requirements of the 50MeV proton cyclotron. From the facility commissioning to the customer's experiment, it only took 15 days. During the 12-hour performance test, all systems operated stably without errors, demonstrating the excellent magnetic field performance of the accelerator and proving the importance and accuracy of the magnetic field measurement device and shimming.

Speaker: fei wang (China Institute of Atomic Energy)

18:10 Development of a 100 MeV Proton Cyclotron for Multi-disciplinary Research at Harbin Institute of Technology

Recently, the Special Environmental Science and Application Infrastructure for Materials and Devices (SEMD), proposed by Harbin Institute of Technology (Shenzhen), has commenced construction. It is dedicated to investigating the mechanisms governing the influence of special service environments on materials/devices. Within the SEMD facility, a medium-to-high-energy Proton Irradiation Research System has been initiated. It aims at creating a multi-disciplinary R&D platform and bringing together various scientific communities around a high-intensity isochronous cyclotron with beam energies up to 100 MeV (upgradable to 150 MeV). A compact cyclotron scheme for accelerating H- ions with four straight sectors has been adopted. Its magnet is designed to have a height of approximately 2 meters and a radius of around 3 meters, with a maximum magnetic field of 1.4 T. Two half-wave RF cavities are installed in the valley regions of the magnet, and its working frequency is around 45.7 MHz. H- beams will be accelerated and then extracted via carbon stripping foils. By optimizing their positions, we hope to obtain proton beams with energies varying from 30 MeV to 100 MeV. A multi-cusp ion source has been selected in order to get a high beam current at the experimental terminals. The output intensity is designed to be 500 μA in maximum and the intensity required for stable operation is about 150 μA. In the main text, we will introduce the preliminary design work completed so far.

Speaker: Bowen Bai (Harbin Institute of Technology Shenzhen Graduate School)

18:10 Digital Soft Square Wave Generator

This research focuses on making compact cyclotrons genuinely reconfigurable without hardware changes (matchbox) with digitally timed, wide-range RF/voltage source.
We propose a concept that introduces a digitally agile acceleration-voltage source that replaces an analogue sinusoidal RF drive with a programmable, soft-edged square-pulse waveform. The Digital Soft Square Wave Generator (DISWAG) approach utilizes an FPGA-driven logic unit and a high-frequency Class-D power stage to generate precisely timed voltage pulses, leveraging Zero-Voltage Switching (ZVS) to minimize switching losses alongside a custom-made transformer. This concept allows for the generation of a nearby rectangular signal which further optimizes the performance.
Key design targets include operation in the low MHz range (around 2-4 MHz acceleration frequency) and kilovolt-level output to match the needs of multi-keV compact cyclotrons. Initial simulations and GaN transistor tests have affirmed the feasibility of this approach, demonstrating stable MHz switching with lower thermal losses. The digital waveform can be retuned during functionality to accommodate different isotopes and beam conditions.

Speaker: Sepehr Farid (Coburg University of Applied Sciences)

18:10 Effects of Low to Medium Dose Proton Irradiation on Gut Microbiota in BALB/c Mice

Proton radiation dominates space radiation (∼90%) and threatens deep space missions, yet its effects on gut microbiota at mission-relevant doses (0.1-1 Gy) are unclear. This study assessed impacts in BALB/c mice exposed to whole-body proton irradiation (0, 0.1, or 1 Gy; 100 MeV cyclotron). Fecal samples (day 3 post-irradiation) underwent 16S rRNA sequencing. Results revealed a dose threshold: 1 Gy induced significant structural remodeling, marked by increased Firmicutes (56.93% vs. control 32.23%), decreased Bacteroidetes (3.95% vs. 27.95%), a 116% higher Firmicutes/Bacteroidetes ratio, and enrichment of biomarkers Lachnospiraceae NK4A136 (LDA=4.2) and denitrifiers (LDA=3.8). Conversely, 0.1 Gy caused minor changes (Rikenellaceae, LDA=3.5; Odoribacter, LDA=3.3). Critically, 1 Gy enhanced alpha diversity (Chao1 +15-20%, Shannon +11.3%; p<0.05) and altered beta diversity (R²=0.251-0.361, p<0.05) versus controls. Functional prediction (PICRUSt2) identified disruptions in cellular processes/signaling (p=0.0133), poorly characterized pathways (p=0.0298), ABC transporters (K03088, p=0.021), and fatty acid metabolism (K02003, p=0.045). These findings demonstrate that gut microbiota exhibits differential dose-response patterns to proton radiation, which provide both reference biomarkers and mechanistic insights for evaluating astronaut intestinal health risks and developing microbiota-targeted countermeasures during deep space missions.

Speaker: Zirui Chen (China Institute of Atomic Energy)

18:10 Electron Accelerator-Based Co-Production Method for Multiple Medical Isotopes via Molten Salt Targets

Medical radioactive isotopes play an increasingly critical role in nuclear medicine. Accelerator-based production of medical isotopes offers advantages including simplified regulatory approvals, operational flexibility, system safety, and lower costs, making it an important production method. This study proposes a multi-isotope co-production system utilizing electron accelerators. The methodology employs direct electron beam irradiation of molten salt targets, obviating the use of conversion targets, thereby improving beam utilization efficiency. The unique flow characteristics of liquid molten salt targets provide superior thermal management capabilities, effectively addressing heat dissipation limitations of solid targets while enabling continuous online extraction potential. Compared to solid target systems, the liquid target system significantly simplifies target fabrication procedures. Additionally, this methodology allows simultaneous production of multiple medical isotopes through compositional adjustment of the molten salt, improving production efficiency. This study employed FLUKA Monte Carlo simulations to optimize the structural parameters of the molten salt target and evaluate the yields of medical isotopes. The results revealed that the saturation yields of the target medical isotopes reached: Tc-99m (48.77 Ci), Mo-99 (55.77 Ci), I-131 (17.41 Ci), and Sr-89 (8.35 Ci). This method provides a new approach and reference for the production of medical isotopes.

Speaker: Junze Lin (Shanghai Institute of Applied Physics)

18:10 Feasibility Study on the Further Miniaturization of AVF Cyclotrons

The use of AVF cyclotrons for proton therapy in hospitals has been on the rise in recent years. However, further miniaturization is essential for wider adoption. Our company has previously succeeded in reducing the size of conventional AVF cyclotrons for proton therapy to approximately 60% of their original dimensions by implementing superconducting technology.
While synchrocyclotrons are relatively easy to miniaturize, AVF cyclotrons offer the advantage of continuous beams with high average beam current. This contributes to shorter treatment times, enabling less burdensome therapy for patients.
In this report, we present the results of a physical study on further miniaturization of superconducting AVF cyclotrons, focusing on aspects such as isochronism and beam extraction.

Speaker: Dr Hiroshi Tsutsui (Sumitomo Heavy Industies, Ltd.)

18:10 Fringe Field Effects and Their Mitigation in Magnetic Lens Systems for Proton Radiography

The imaging accuracy of proton radiography critically depends on the beam transfer matrix defined by magnetic lenses. However, fringe field effects introduce nonlinear magnetic components, causing deviations from the ideal hard-edge model and limiting the performance of con-ventional optics designs. In this study, we systematically investigate methods for precise characterization and mitigation of magnetic lens fringe fields for an 18 MeV proton radiography experimental platform. Pole-face shimming and end-cutting techniques are applied to suppress higher-order harmonics and enhance field uniformity within the effective region. The fringe field distribution is further quantified using a three-dimensional Enge coefficient fitting method and incorporated into beam optics matching software for accurate simulation. Based on point-to-point imaging performance, the quadrupole magnet structure and gradient strength are co-optimized. Full-scale particle tracking simulations validate the effectiveness of the proposed design, demonstrating high imaging fidelity under realistic fringe field conditions. This work provides a reliable technical approach for the optimized design of high-precision proton radiography lens systems

Speaker: shuangxin li (Huazhong University of Science and Technology)

18:10 Hybrid Autoencoder and Isolation Forest Approach for Time Series Anomaly Detection on ARRONAX Cyclotron Operation Data

The Interest Public Group ARRONAX's C70XP cyclotron, used for radioisotope production for medical and research applications, relies on complex and costly systems that are prone to failures, leading to operational disruptions. In this context, research is being conducted to develop an active machine learning method for early anomaly detection to enhance system performance. One of the most widely recognized methods for anomaly detection is Isolation Forest (IF), known for its effectiveness and scalability. However, its reliance on axis-parallel splits limits its ability to detect complex anomalies, especially those occurring near the mean of normal data. This study proposes a hybrid approach that combines a Multi-Layer Perceptron Autoencoder (MLP-AE) with Isolation Forest to enhance the detection of complex anomalies. The Mean Squared Error (MSE) of the data reconstructed by the MLP-AE is used as input to the IF model. Validated on beam intensity time series data, the proposed method demonstrates a significant performance improvement, as indicated by the evaluation metrics, specifically the Area Under the Precision-Recall Curve (AUC-PR) and the F1 score.

Speaker: Fatima Basbous (Nantes Université)

18:10 Impact of Magnetic Field Imperfections on Beam Dynamics in a High-Intensity Compact Cyclotron

Compact high-intensity cyclotrons are increasingly important for isotope production worldwide. The SK1000 is a proposed superconducting cyclotron designed to accelerate H₃⁺ ions to 120 MeV/u. It features a large main magnet with a height of 2.99 m, a diameter of 7.58 m, and an outer sector radius of 2.25 m. The manufacturing and installation of a magnet of this scale inevitably introduce field imperfections. This study investigates the effects of such magnetic field errors on beam dynamics to inform magnet mapping and shimming strategies. Through combined analytical and numerical simulations, we establish tolerance limits for magnetic field errors. Special attention is given to the resonances νᵣ = 1, driven by first harmonic field errors, which lead to radial emittance growth. Resonances contributing to vertical emittance growth are also examined. Finally, we present the maximum allowable magnetic field errors that ensure stable beam operation in the SK1000 cyclotron.

Speaker: Xi Chen (Institute of Modern Physics, Chinese Academy of Sciences)

18:10 INFN-LNS Superconducting Cyclotron upgrade: Magnetic field mapping results

The upgrade of the Superconducting Cyclotron at INFN Laboratori Nazionali del Sud in Catania is aimed at improving its performance in terms of intensity of light ions, as well as in terms of reliability. In the framework of the upgrade, a key milestone has been the magnetic field measurements of the new superconducting magnet, with the following goals: a) to implement a measurement procedure able to quantify and correct errors due to coils misalignment; b) to validate the field quality in the symmetry plane evaluating the differences between the measured and theoretical values.
The measurement procedure started in February 2023 at ASG Superconductors company. The first measurement campaign was performed with coils at room temperature: it was necessary to align them with respect to the ideal symmetry plane minimizing the undesired field harmonics contents. Moreover a post-processing tool has been developed to obtain the best coils centering. The second phase has been performed considering the same measurements set with the coils operating inside the cryostat filled with liquid helium at 4.2 K. The magnetic measurements mapping data are here presented.

Speakers: Mr Antonio Domenico Russo (Istituto Nazionale di Fisica Nucleare, Laboratori Nazionali del Sud), Dr Giorgio Mauro (Istituto Nazionale di Fisica Nucleare, Laboratori Nazionali del Sud), Dr Danilo Rifuggiato (Istituto Nazionale di Fisica Nucleare, Laboratori Nazionali del Sud)

18:10 INJECTION AND CENTRAL REGION DESIGN OF LB-30TP CYCLOTRON

Sichuan Longevous Beamtech is currently developing a new tri-particle cyclotron LB-30TP. The LB-30TP cyclotron is designed to be able to accelerate protons(H-) between 13 and 35MeV, deuterons(D-) between 6.5 and 17.5MeV, and alpha particles(He2+) up to 30MeV.
The proton and deuteron beams are generated by a multi-cusp ion source, while the alpha particle beams are generated by an ECR ion source. These two ion sources are located on two sides above (or below) the cyclotron, and the ion beams extracted from them are both transported through a primary focusing solenoid and combined by a dipole before entering the injection beam line. The injection beam line consists of a quadrupole triplet, a steering magnet, a solenoid and a quadrupole doublet, and the matching between the beam emittance and the acceptance at the entrance of the spiral inflector is achieved by optimizing the parameters of these magnetic components. The spiral inflector and the central region electrodes are optimized to achieve high injection efficiency and good orbit centering.

Speaker: ZHEN SHEN (Sichuan Longevous Beamtech Co., Ltd)

18:10 Magnetic Field Design and Uniformity Control for Isochronous Multi-Plane Cyclotron Orbits under a Common Magnet System

In pursuit of enhanced beam current and spatial efficiency in high-intensity cyclotrons, this study investigates a novel accelerator concept: the use of multiple axially separated orbits (multi-plane) operating under a common magnet system. A key challenge in such a configuration is maintaining isochronism across distinct axial planes, which critically depends on the uniformity of the magnetic field in the vertical z direction. This work presents a theoretical framework and numerical approach to quantify the magnetic field uniformity requirements necessary to preserve isochronous conditions for multi-plane orbits. An analytical framework is proposed to construct a 3D static magnetic field model of an axisymmetric multi-layer magnet, incorporating excitation coils and their positioning. The model focuses on the magnetic field distribution across multiple parallel orbit planes. Field distributions are evaluated on three parallel orbit planes (z = −Δz, 0, +Δz), and the deviation of magnetic induction δB(z)=(Bz−B0)/B0 is analyzed. Based on classical isochronous criteria, a quantitative threshold for the vertical field gradient ∂B/∂z is derived to ensure phase stability within ±10⁻³ relative deviation. This study provides design guidelines and performance limits for implementing synchronized multi-plane orbit systems within a single magnet, offering a pathway toward compact, high-current cyclotron architectures.

Speaker: Prof. Zi-Feng He (Shanghai Institute of Applied Physics)

18:10 METAMATERIAL-EMBEDDED CAVITY BEAM CURRENT MONITOR FOR PROTON THERAPY

Cyclotron-based proton therapy systems have become the mainstream equipment in modern radiation oncology. Their therapeutic efficacy critically depends on the precise control of key beam parameters such as intensity and energy. In clinical applications, energy modulation is typically achieved by a degrader. However, it inevitably induces large dynamic fluctuations in beam intensity. In addition, long-term operation of the accelerator often introduces thermal drifts, which lead to undesired energy instabilities. Thus, high-precision, real-time beam diagnostics and feedback control technologies are essential for accurate dose delivery in proton therapy.
To address this, we propose a re-entrant resonant cavity detector based on metamaterials. This design enables flexible electromagnetic parameter engineering and internal field reconstruction. It reduces operating frequency, enhances field confinement and achieves miniaturization while maintaining a high quality factor. Theoretical and simulation results confirm a uniform central electric field distribution with superior amplitude resolution over conventional cavities. The detector supports high-precision diagnostics under large beam variations and enables synchronous, real-time monitoring of bunch phase, intensity and energy. This work demonstrates the feasibility of metamaterial-based compact cavity detectors for medical accelerators, promising enhanced robustness in clinical proton therapy through accurate beam monitoring.

Speaker: Yuexin Lu (Huazhong University of Science and Technology)

18:10 Parameter Analysis and Optimization for Ion Source of Accelerator

Ion source is an important subsystem in accelerators, which employ electromagnetic fields to accelerate charged particles to generate ion beams. Accelerators are essential facilities for advancing multidisciplinary research and developing technological applications, such as production of medically relevant radioisotopes and ion beam irradiation of cyclotrons. Among the various ion source technologies, the 2.45 GHz ECR (Electron Cyclotron Resonance) ion source demonstrates significant potential due to its ability to generate dense plasma and deliver high beam current. To systematically investigate and optimize its performance, coupled numerical simulations were used to analyze the key parameters of both the plasma chamber and the extraction system, and get the results of plasma density, ion fraction, beam current and quality. With the optimized design, the current increases by 42.4%, the emittance decreases by 21%, and the beam spot decreases by 32.9%, meeting the requirements of accelerating structure, and providing important theoretical data for the beam commissioning. This work also offers some critical insights for the development of high current, low emittance, and high stability ECR ion sources.

Speaker: Guangzhao Huang (Shandong University, International Academy of Neutron Science)

18:10 Plasma-Assisted Neutralization in Axial Injection for High-Current Compact Cyclotrons

High-current compact cyclotrons face strong space-charge limitations during axial injection, where the low-energy proton beam expands before reaching the inflector. We present a novel plasma-assisted neutralization module designed as a drop-in element between the final solenoid and the inflector entrance. The device consists of a short solenoid surrounding a beamline cell operated at controlled pressure. Residual hydrogen gas $(H_2)$ or an injected noble gas $(Kr)$ is ionized by the high-current proton beam to form a self-sustaining plasma column. Biased end-electrodes confine electrons and accelerate neutralization, achieving effective space-charge compensation. Krypton seeding provides a faster build-up of neutralization relative to $H_2$, enabling rapid stabilization for pulsed or ramped operation. Simulations and analytic estimates indicate that neutralization substantially reduces transverse beam blow-up while introducing only modest multiple scattering over the short transport distance. The concept offers a compact, plasma-based method to increase capture efficiency for milliampere-class proton beams and provides a tunable platform to investigate plasma–beam interaction effects in cyclotron injection lines. Initial design parameters, integration strategy, and predicted performance are presented.

Speaker: Chong Shik Park (Korea University Sejong Campus)

18:10 Preliminary Design of a Cyclotron Measurement and Control System with Distributed Acquisition/Control and Centralized Storage

To address the requirements of modern cyclotrons for high-precision, high-reliability, and high-scalability operation and experimentation, as well as to overcome the limitations of traditional centralized measurement and control systems—such as high single-point failure risks, poor scalability, and bottlenecks in mass data processing and storage—this paper proposes and preliminarily designs a hierarchical system architecture based on "Distributed Acquisition/Control + Centralized Data Management."

The system employs a unified underlying database framework, a unified timing system, and a unified time series as its software core. At the hardware level, a distributed network consisting of multiple acquisition and control nodes is constructed. These nodes are responsible for locally collecting real-time data from subsystems (e.g., magnetic field, RF, vacuum, beam diagnostics) and executing efficient local closed-loop control, with communication facilitated via high-speed Ethernet. At the software level, channel access protocols enable efficient and reliable data communication and interaction among distributed nodes.

Speaker: 勇 章 (Hefei Institutes of Physical Science)

18:10 Reaccelerating Muons at PSI

Muon beams are powerful research tools with applications in both particle physics and condensed matter physics. However, surface muon beams suffer from high emittance. Several facilities (PSI, RAL, J-PARC) are developing cooling devices to mitigate this issue, but these devices inevitably reduce the beam’s kinetic energy. To address this challenge, the project explores a compact muon cyclotron design, adapted from the IsoDAR project, to reaccelerate muons emerging from the MuCool device. Preliminary OPAL simulations show promising results.

Speaker: Andreas Adelmann (Paul Scherrer Institute)

18:10 Research on parameter optimization of uniforming transport lines based on deep reinforcement learning

Beam transport line of uniformization is an essential step before beam shooting and plays a critical role in applications such as neutron imaging and isotope production. In practical experiments, particle beams generated by cyclotrons typically exhibit an approximately Gaussian intensity distribution. Local bright spots on the targets for high-power Gaussian beams create difficult cooling problems and shorten the lifetime of the target. To address this issue, a beam transport line with multiple beam elements is designed. Considering the complexity of multi-parameter optimization process, an automatic optimization method based on deep reinforcement learning is investigated. In the simulation environment, the Soft Actor-Critic ( SAC ) algorithm is employed to adjust multiple beam elements for optimizing the uniformity of the beam. Results indicate that the SAC algorithm based on the maximum entropy principle achieves over 85% uniformity on the target. Compared with manually optimizing parameters, the proposed method demonstrates higher efficiency and superior uniformization performance.

Speaker: Mr Yuzhuo Huang (China Institute of Atomic Energy)

18:10 Results and Developments of PEPITES, a Transparent Profiler based on Secondary Electrons Emission for Charged Particle Beams.

The PEPITES profiler was originally designed for continuous operation on medium-energy (O(100 MeV)) charged particle accelerators. Its ultra-thin structure relies on secondary electron emission (SEE) to generate signals. It has successfully measured the positions and profiles of various hadron beams across a wide dynamic range.
This innovative device consists of 50 nm gold strips deposited on a radiation-resistant polyimide substrate. Secondary electrons emitted from the strips gold surface form the signal. Thanks to the high linearity of the SEE, the profiler enables accurate characterization of continuous beams as well as pulsed beams across a wide dynamic range, without the saturation effects commonly observed in other detectors. Additionally, the design minimizes beam perturbation while ensuring excellent durability, even under demanding operating conditions.
A first PEPITES prototype was installed and has been routinely used at ARRONAX to measure beam profiles of 70 MeV proton beams in both continuous and pulsed delivery modes. Furthermore, preliminary tests conducted at the CNAO** hadrontherapy center with therapeutic-energy protons and carbon ions have produced promising results, confirming the device’s compatibility with a broad range of beam types, energies and intensities.
These results position PEPITES as a promising and transformative solution for beam monitoring in both current and next-generation hadron beam facilities.

Speaker: Christophe Thiebaux (Laboratoire Leprince-Ringuet, CNRS-Institut Polytechnique de Paris, Ecole polytechnique)

18:10 RF Cavity Design of a High-current H2+ Compact Cyclotron

A new technology research of a high-current H2+ small cyclotron is in progress at China Institute of Atomic Energy. The cyclotron is designed based on a RFQ injection line, which is expected to break through the current limit of the small cyclotron and bring the current of the small cyclotron to above 3mA. This project is designed to achieve a particle energy of 10MeV, and the theoretical design of each system has been completed, preparing to enter the manufacturing stage. This paper mainly introduces the design and research work of the radio-frequency cavity. In order to increase the energy gain per circle to reduce the beam loss, we choose the fourth harmonic, four cavities scheme. Each cavity is a half-wave coaxial resonator, and the four cavities are in the same phase. In order to reduce the complexity of the system, we use a single transmitter to drive the four cavities, and the four cavities are connected together through the head of the Dee plate . This paper expounds the simulation process of the electromagnetic field of the cavity, the optimization process, and the multi-physics
coupling analysis of the cavity. Finally the resonant frequency of the cavity is designed as 36.5MHz, and the quality factor is 5000. The acceleration voltage of the cavity gap is 40kV on average， and the total power loss of the four cavities is 18kW. The design results of the cavity meet the technical requirements， laying the foundation for the construction of project.

Speakers: yaqing wang (China Institute of Atomic Energy), Bin Ji (China Institute of Atomic Energy)

18:10 Secondary Electron Suppression Analysis in Accelerator Based Neutron Source

Accelerator based neutron sources generate a large number of secondary electrons during operation. For example, secondary electrons generated by cyclotrons will change the spatial distribution of the beam and reduce the stability of the beam. Secondary electrons generated by neutron generators will flow back to the ion source, increase the load of the high-voltage power supply, and affect the safety and stability of the equipment. For neutron generators, this paper uses numerical simulation methods to study the impact of different electric field parameters on secondary electron suppression. The results indicate that when the target voltage is fixed at 120 kV and the bias voltage changes from 600 V to 900 V, the target current decreases from 41.6 mA to 30 mA, indicating that the secondary electrons are completely suppressed. Meanwhile, when the bias voltage is set to 600 V, the target current increased from 30 mA to 41.5 mA as the target voltage was raised. Additionally, a greater inclination angle of the acceleration electrode and a closer baffle to the target can be also effective for the suppression of secondary electrons, the target current decreased from 41.6 mA to 38.2 mA when the inclination angle increased from 84º to 96º, furthermore, the lowest target current could be obtained at the inner baffle distance of 20 mm. This work provides theoretical guidance for the optimization of accelerator neutron sources.

Speaker: Xuebao Chen (Shandong University, International Academy of Neutron Science)

18:10 Simulation Study on Beam Extraction Efficiency of HIRFL-SSC

The HIRFL-SSC employs a resonance free extraction method. In the h=4 mode, the larger turn separation allows for single-turn extraction and the extraction efficiency is high, whereas in the h=2 mode, the smaller turn separation results in lower extraction efficiency. To improve the SSC transmission efficiency, simulations were conducted to analyze the extraction efficiency and acceptance under two typical modes (h=2 and h=4). The calculations reveal that the beam size growth caused by the injection phase width is a critical factor limiting the SSC extraction efficiency. To enhance the extraction efficiency in h=2 mode, a simulation study was performed on off-equilibrium orbit injection to achieve "radial focusing" of large-phase-width ions. The simulation results demonstrate that this method can significantly improves the SSC extraction efficiency compared to the old extraction approach.

Speaker: MeiTang Tang (MeitangTang, Institute of Modern Physics)

18:10 The effect of different doses of proton radiation on the transcriptomic profiling of vascular endothelial cells

With the development of the aerospace industry, the duration of astronauts' stay in space has significantly increased, and space radiation has become one of the major threats to their health. Vascular endothelial cells are relatively sensitive to ionizing radiation, and their dysfunction is closely associated with the occurrence of cardiovascular diseases. Currently, the damage mechanism of proton radiation to organisms, especially to the cardiovascular system, remains unclear. In this study, human umbilical vein endothelial cells (HUVEC) were used as the research object. Relying on the 100 MeV proton cyclotron at the China Institute of Atomic Energy, HUVEC were irradiated with protons at four doses of 0.25, 0.5, 0.75, and 1 Gy. The effects on the results of cell transcriptional sequencing in each dose - group were detected and analyzed. Differential gene expression analysis showed that the number of differentially expressed genes increases with the rise in dose. GO and KEGG enrichment analysis results indicate that at the 0.25 Gy dose, cells exhibit a pro-inflammatory and anti-inflammatory balance. At the 0.5 Gy dose, inflammatory responses remain enriched while the necrotic apoptosis pathway is activated. At the 0.75 Gy dose, immune-inflammatory dysregulation occurs. At the 1 Gy dose, immune-inflammatory dysregulation intensifies alongside DNA damage enrichment.
Keywords: proton radiation, HUVEC, inflammatory damage, transcription sequencing analysis

Speaker: zhihao huang (China Institute of Atomic Energy)

18:10 The Extraction of Positively Charged Proton Beam from Cyclotron due to Energy Loss at the Degrader

For modern medical cyclotrons the acceleration of beams of negatively or positively charged protons is most widespread. As a rule, negatively charged ions are extracted from cyclotron by recharging on a thin carbon foil. It is a easy realization method. However, to produce negatively charged protons, a complex system of external injection is usually used. Besides, the effect of electromagnetic dissociation of an electron during acceleration limits the level of cyclotron magnetic field. Positively charged ions are produced by simple internal Penning type ion source and there are no limits in a magnetic field level. However, the extraction of such a beam from a cyclotron is possible only by a complex extraction system with an electrostatic deflector and passive or active focusing elements.
At the paper the extraction of positively charged proton beam by means of partial decreasing of energy at degrader are considered. The proposed method combines the positive features of described above schemes, such as easy of ions production, unlimitation of the magnetic field level and easy technical realization of extraction system. The obvious disadvantage of this method is the increasing of the beam emittance after passing through the degrader.
As an example, a three sector cyclotron with a magnetic field level of 1 T to accelerate of positively charged protons to an energy of 15 MeV is proposed. The beam extraction is carried out due to 5 - 10% energy loss on a graphite degrader.

Speaker: Ivan Ivanenko (Joint Institute for Nuclear Research)

18:10 The performance research of the Beam Shaping Assembly (BSA) materials used for BNCT based on the cyclotron

Cancer has become one of the important factors threatening human life and health, and methods for treating cancer are constantly being studied and explored. It is an urgent demand in the healthcare to treat cancer by rays. Boron Neutron Capture Therapy (BNCT) is given increasing amount of attention due to its ability of selective cancer cell killing. The BNCT neutron source based on the 18 MeV/1 mA cyclotron is researched. To improve the flux of the epithermal neutrons, simultaneously reducing fast neutron dose as much as possible, this paper studies the generation and transport of neutrons in the Beam Shaping Assembly (BSA) of the BNCT. By comparing reaction cross sections (including neutron multiplied reaction, neutron inelastic scattering and neutron elastic scattering) of different materials, the materials of neutron multiplier and neutron moderator are researched. In this study, Be is chosen as the target to produce neutron by 9Be(p,n)9B reaction. Pb is chosen as neutron multiplier. LiF or MgF2 is chosen as neutron moderator. Ni is chosen as fast neutron filtration material. The neutron yield can achieved 5.25×10^13 n/s. The epithermal neutron flux is 2.92×10^9 n/cm2/s, with the fast neutron dose of 5.87×10^-13 Gy·cm2 per epithermal neutron.

Speaker: lu lu (China Institute of Atomic Energy)

18:10 Thorium-based Molten Salt Fast Energy Amplifier Reactor-accelerator Coupling and Beam Window Design

Abstract: As a fourth-generation nuclear reactor concept, molten salt reactors (MSRs) have unique advantages in safety, economy, and nonproliferation, but online fuel salt treatment remains immature. To avoid complex online fuel treatment, the Thorium-Based Molten Salt Fast Energy Amplifier (TMSFEA) concept was proposed. Compared with traditional Accelerator-Driven Subcritical (ADS) systems, the TMSFEA reactor operates at a higher temperature (over 600 ℃), which enables higher thermal efficiency but also imposes stricter requirements on reactor-accelerator coupling design. Thus, a study on TMSFEA’s reactor–accelerator coupling design was conducted: the beam window was isolated from liquid molten salt, with a 2-meter-long helium column inserted between them for protection at standard atmospheric pressure. A beam window structure was designed, featuring single-layer films on both sides and a double-layer film with cooling water flow in the middle, and the effects of parameters like film radius and thickness on the proton beam window’s temperature rise and thermal stress were analyzed. After optimization, the beam window film’s maximum temperature and thermal stress were 42.5 ℃ and 66.4 MPa, respectively. FLUKA was used to analyze the beam window’s radiation damage. Under 1 GeV/4 mA beam current and one-year continuous operation, the calculated value of DPA per year is 0.008 DPA. The safe operating life of the beam window exceeds the 39-year safe operating life of the TMSFEA.

Speaker: Hao Li (Shanghai Institute of Applied Physics)

18:10 Upgrade of the RF Control System for the K-800 Superconducting Cyclotron at INFN-LNS

INFN-LNS is proceeding with the upgrade of the Superconducting Cyclotron. The final goal is to increase the extraction efficiency in order to achieve a beam power up to 10 kW. The RF systems are also undergoing significant improvements through several upgrades. The new control system architecture will be able to manage the LLRF system, HLRF devices, and beam pulsing systems. The new software allows more accurate management of all RF parameters and centralized control of peripheral devices. This architecture enables simultaneous control of cavity phase, amplitude and tuning loops, monitoring of power amplifier parameters, protection and fault diagnosis, and integration with various acquisition and measurement systems. The power amplifiers and drive systems involved in the tuning and coupling of the resonant cavities have also undergone substantial refurbishment. All these developments are detailed in this paper.

Speaker: Mr Antonio Domenico Russo (Istituto Nazionale di Fisica Nucleare, Laboratori Nazionali del Sud)

18:10 Upgrades On The Cyclotron Injection Line at SPES Facility at LNL

The 70 MeV cyclotron in use at Laboratori Nazionali di Legnaro at INFN was designed to deliver proton current up to 0.75 mA. Being designed as a relatively high current cyclotron, little attention was dedicated to the possibility to operate at low currents in the order of few tens of nA. On the other side, it is very interesting to try to increase the deliverable current near or above the 1 mA range.
Experiments planned at the SPES facility require operation at low currents. To be able to operate at such currents in a fail safe mode, a chopper is being designed for the injection line.
To increase the current, on the other hand, a beam buncher is being designed for the injection line.
Beam dynamics simulations and both mechanical and electronics design will be discussed.

Speaker: Piergiorgio Antonini (Istituto Nazionale di Fisica Nucleare)

18:10 ZycloSim 2000 – A Simulation Program for Ion Dynamics in a Classical Cyclotrons

We present ZycloSim 2000, a software package developed to simulate the motion of ions in a classical, non-relativistic cyclotron. The program is primarily designed for educational purposes and is employed in workshops and laboratory courses to illustrate cyclotron dynamics and to investigate the resonance condition in detail.
The code allows the user to adjust a wide range of parameters, including ion species, magnetic flux density, and the frequency and amplitude of the accelerating voltage, thereby enabling systematic studies of their influence on particle trajectories. Key trajectory data (e.g. radius, velocity, path length) are calculated and can be visualized through five different types of plots. In addition, data export facilitates further analysis with external software such as Excel, MATLAB, or Octave.

Speaker: Christian Wolf (Hochschule für Angewandte Wissenschaften Coburg)

Tuesday 28 October

08:30 → 10:00 Cyclotron and Technology (1): Session TUA

Convener: Dr Danilo Rifuggiato (Istituto Nazionale di Fisica Nucleare, Laboratori Nazionali del Sud)

08:30 New Generation High Intensity Proton Cyclotron using H3+ Ions

We propose a new class of compact superconducting cyclotrons based on the stripping of H3+ ions. In this method, H3+ ions are accelerated and pass through a thin carbon foil, where the electrons are removed to produce three protons per ion. Compact cyclotrons require high magnetic fields, which makes H- acceleration impractical; H3+ ions, however, can possibly tolerate much higher fields and are therefore suitable for this approach. The stripping technique offers very high extraction efficiency, enables variable-energy proton beams, and allows simultaneous delivery to multiple production targets. These features make such machines highly attractive. We aim at proton energy of 70–150 MeV and proton current of ~1.0 mA, which remains largely undeveloped worldwide. Our study focuses on beam dynamics, particularly the large acceptance required for high-intensity beam and feasibility of single-turn extraction to minimize beam losses. A baseline design and preliminary results are presented.

Speaker: Yi-Nong Rao (TRIUMF)

09:00 Steps towards a 1.6μA extracted beam of the CYCIAE230 superconducting cyclotron for proton therapy

A superconducting cyclotron, the CYCIAE230, has been developed by CIAE of CNNC for proton therapy applications over the past few years. The beam commissioning of this machine was completed previously, in 2023. A series of improvements were carried out in the early part of this year to increase the stability and beam intensity of the cyclotron for potential FLASH usage. It includes optimizing the ion source to achieve higher intensity, optimizing the phase selection in the central region, and aligning the primary coil, as well as adjusting the location of the electrostatic deflector, among other factors. In the meantime, several measures have also been taken to improve cyclotron subsystem stability, including enhancements to the RF system and improvements in beam diagnostics, such as the time structure and beam phase. A dedicated beam tuning software has been developed to adapt to the needs of cyclotron beam fine-tuning. It provides a feature that displays all parameters on a single page, which facilitates beam tuning activity. All these technical adjustments combined led to an overall extraction beam current of up to 1.6 μA. Afterward, the radiation distribution analysis and relocation of the cyclotron accessory device were performed according to the configuration of the short-term runs. The optimization measures, improvements to the subsystems, and beam tuning results will be reported in this paper, along with the dedicated beam tuning software.

Speaker: Zhiguo Yin (China Institute of Atomic Energy)

09:20 Gyrating Ion Beam Driven Whistler Wave Instability in a Dusty Plasma

This manuscript examines the non-linear interaction between the negative energy beam cyclotron mode and high-frequency whistler waves. The negative energy beam mode is supported in the vicinity of the beam gyro-frequency harmonics by a gyrating ion beam with
ring shaped velocity distribution. Using a gyrating ion beam, we have examined how dust charge variations affect the parametric up-conversion of high frequency whistler waves (WW) into an side band wave and a low-frequency mode. For the linked modes, a non-linear dispersion relation is obtained. It is demonstrated that whistler waves divided by beam gyro-frequency harmonics are up-converted by a gyrating ion-beam frequency. A formula for the ion cyclotron mode wave growth rate has been obtained. The estimation of the turbulence growth rate takes into account for the typical parameters of an existing dusty plasma. It is detected that an increased growth rate appears with a rise in the pump wave amplitude, beam gyro-frequency, number density of dust grains, and the relative density of dust grains. However, a decline in the growth rate has been detected with increasing gyrating ion beam density and dust grains size.

Speaker: Amit kumar (Amity University)

09:40 Design of the RF Cavity for 30 MeV Alpha Particle Cyclotron

Alpha particle accelerators hold significant potential for applications in the production of medical radioisotopes, particularly demonstrating unique advantages in obtaining At-211 medical radioisotope, which is difficult to produce via traditional neutron reactions, such as reactor neutron irradiation. In this paper, a high-frequency resonant cavity operating at 36.8 MHz was designed for a 30 MeV alpha particle cyclotron and multi-physics simulations were employed to analyze the electromagnetic characteristics, thermal distribution, mechanical deformation and frequency deviation of the cavity. Through the implementation of a deep-valley and stepped-impedance coaxial cavity, 36.8 MHz frequency resonance was achieved within a relatively compact volume while maintaining high Q-factor and low power consumption at 90 kV accelerating voltage. Furthermore, an inductive power coupler was placed near the short-circuit wall that was avoided in the constrained engineering environment. The reflection coefficient of RF coupler can be adjusted to below -35dB by rotating power coupler, which indicates excellent matching. The maximum electric field strength and thermal stress of water-cooled RF window during high-power operation have been analyzed. The engineering design will be informed by the physical analysis of RF cavity,which will be finished before 2026.

Speaker: Dr Xin Zhang (University of Science and Technology of China)

10:00 → 10:20 Coffee break

10:20 → 12:00 Theory, Models, Simulations and AI Applications in Cyclotron (2): Session TUB

Convener: Andreas Adelmann (Paul Scherrer Institute)

10:20 Reinforcement Learning for Real-Time Cyclotron Tuning: Results from the Injector 2 Experiment at PSI

Achieving reliable, fast, and reproducible cyclotron tuning remains a key operational challenge as accelerators move towards increasingly complex beam configurations and higher intensities. To address this, we conducted a two-week experimental campaign at PSI Injector 2 to evaluate the feasibility of applying reinforcement learning (RL) for real-time beam optimization. These experiments represent an important first step towards automated and reliable cyclotron control, demonstrating the potential of RL-based approaches to improve tuning efficiency and operational stability. We will present the experimental setup, methodology, and safety strategies, highlight key results, and discuss lessons learned for future deployment at high-current HIPA operations.

Speaker: Dr Malek Haj Tahar (TRANSMUTEX)

10:50 FETS-FFA Project at RAL, UK

A Fixed Field Alternating gradient (FFA) accelerator is an option as a proton driver for the next generation spallation neutron source (ISIS-II) in the UK. To demonstrate FFA suitability for high intensity operation, a prototype 3-12 MeV proton ring is proposed at RAL using as injector the ISIS Front End Test Stand (FETS). The lattice of this ring, called FETS-FFA, is more similar to a synchrotron than a cyclotron since it uses FD spiral focusing unit and has a super-period structure to accommodate long straight sections for injection and extraction. Beam stacking is a key technique to increase the peak intensity in an FFA. The design and experimental validation will be shown. The main lattice magnet is the crucial component of an FFA, with necessary operational flexibility of the working point as a function of beam intensity. A wide range of diagnostics were investigated to measure the beam parameters. This talk will review key results of the 2025 Conceptual Design Report (CDR), as well as other aspects of the FETS-FFA project.

Speaker: Dr Jean-Baptiste Lagrange (Science and Technology Facilities Council)

11:20 Design of q/A=1/2 K100 compact cyclotron system for heavy-ion space radiation effects and radiobiology studies

We have designed a q/A=1/2 K100 cyclotron for various applications including the production of medical isotopes and neutrons using high-intensity H2+, D+, He2+ ions at the maximum energy of 25 MeV/u. In addition, with acceleration of fully charge-stripped light heavy ions such as 14N7+, 36Ar18+, we plan to study space radiation effects on semiconductor chips and precision radiobiology by using microbeam as a high-energy microprobe. Both horizontal and vertical microbeam lines have been designed to conveniently accommodate solid and liquid targets, respectively. The beam optics for microbeam was carried out using TRACE-3D, TRANSPORT in linear optics and TURTLE for particle tracking including up to 3rd order. To produce different ion species in wide range of beam currents, ion sources for H2+, D+, He2+ are placed on top of the cyclotron while a high-performing superconducting ECR ion source needs to located on the upper floor with a beam line for charge selection and axial injection. I will present the design of microbeam lines along with the progress on the cyclotron system design.

Speaker: Jong-Won Kim (Institute for Basic Science)

11:40 Machine Learning Applications in Large-Scale Accelerators

Improvements in beam power and current for large-scale accelerators place increasingly strict demands on operational stability. Traditional operation-and-maintenance strategies are becoming insufficient to meet these high-availability requirements. Rapid advances in artificial intelligence offer a new technical paradigm for delivering efficient, reliable accelerator operation. In this study, we combine nonlinear dynamics with modern machine-learning algorithms to develop a robust beam-tuning method. The method is trained in simulation and has been successfully transferred to a real accelerator system. Building on this result, we developed a flexible, AI-driven beam-tuning platform that significantly improves tuning efficiency and operational flexibility. Future work will focus on enhancing algorithm generalization and on advancing an intelligent operation-and-maintenance framework for accelerators.

Speaker: Xunye Cai (Institute of Modern Physics, Chinese Academy of Sciences)

12:00 → 13:30 Buffet Lunch

Buffet Lunch

13:30 → 15:00 Operation and Upgrades（3）: Session TUC

Convener: Dr Malek Haj Tahar (Paul Scherrer Institute)

13:30 Development of High-Intensity Heavy Ion Beams for RIBF’s ECR Ion Source

At RIKEN RIBF, the development of 28-GHz superconducting electron cyclotron resonance ion sources (SC-ECRIS) [1] is crucial for advancing high-intensity beams of various ion species for scientific, industrial and medical applications. To achieve the RIBF upgrade's core goal [2] of extracting a 2-particle ${\mu}$A uranium (U) beam from the superconducting ring cyclotron (SRC), it is essential to develop a novel Charge Stripper Ring (CSR) [3] to significantly enhance charge stripping efficiency, and to generate 300-$\mu$A U$^{35+}$ beam from the SC-ECRIS. To achieve this goal, we are developing several technologies to confine high-electron-temperature, high-density ECR plasma. This includes the introduction of GM-JT cryocoolers exceeding 8W capable of withstanding X-ray heat loads on the SC mirror coils, the development of a gyrotron for ECR plasma heating, and the design of an oven [4] as a solid sample evaporator in the SC-ECRIS. Especially, the oven heated by high current of around 600 A, was designed with careful consideration of stresses caused by the mirror field exceeding 2 T. These advances aim to significantly enhance intensity and stability across a wide range of ion species. Furthermore, to enhance beam quality, a new analysis method using Pepper Pot Emittance Meter (PPEM) was developed [5] for advanced beam diagnostics. This approach facilitates further improvements in the quality of non-Gaussian beams influenced by the complex fringe field of the ECRIS mirror.

Speaker: Takashi Nagatomo (RIKEN Nishina Center)

14:00 Resume of Cyclotron operation of SPES Facility at LNL

In 2024 the SPES project entered in the commissioning phase and the cyclotron has restarted the operation by providing the primary proton beam for the ISOL target. During the shutdown, many ancillary systems of the cyclotron have been upgraded in order to improve the reliability of the machine in view of the full operation mode expected in next years. The upgrades and the status of recent achievements will be presented and discussed in the presentation.

Speaker: Mario Maggiore (Istituto Nazionale di Fisica Nucleare)

14:20 JULIC – Half a Century of Reliable Operation

The cyclotron JULIC at Forschungszentrum Jülich (FZJ), has been operating for over 56 years. It is a remarkable example of innovation, long-lasting technology and reliability. With its high performance and versatility it was an essential part of the FZJ research program in the field of nuclear physics, irradiation experiments for medical, technical and space application and radiation effects in materials and electronics. During JULICs long life many changes and improvements widened its working spectrum. With the superconducting ECR ion source ISIS, JULIC has accelerated highly charged heavy ions up to Ne, enabling nuclear physics research with light towards heavy ions. Since 1993 and with its colliding beams source CBS, JULIC has delivered unpolarized and polarized proton and deuteron beams to the Cooler Synchrotron COSY and its hadron physics research program and for the JULIC-Neutron Platform with pulsed beams of cold to fast neutrons. Even with operation of proton and deuteron beams mainly, JULIC hasn't lost its ability to run with other species as shown with acceleration of He-3-beams lastly. The technical improvements made to the JULIC systems over the years, like the adaptation of the diagnostic and timing system to meet different experimental needs or transition to an oil-free vacuum system are just a few of the many, led to its high reliability and operational efficiency. Thus all is a testimonial to the ingenuity and dedication of the FZJ staff who made it possible.

Speaker: Dr Olaf Felden (Forschungszentrum Jülich)

14:40 Recent Developments of the TRIUMF 520 MeV Cyclotron

The TRIUMF 520 MeV cyclotron continues to serve as a reliable driver for high intensity proton beams, supporting a broad range of applications. To sustain and enhance high intensity operation, recent developments have focused on reducing beam losses and improving overall reliability. This talk will highlight progress in cyclotron tune optimization and the avoidance of linear coupling resonances to suppress beam spills and reduce component activation.

Speaker: lige zhang (TRIUMF)

15:00 → 15:20 Coffee break

15:20 → 16:30 Operation and Upgrades（3）: Session TUD

Convener: Kuanjun Fan (Huazhong University of Science and Technology)

15:20 Solid state VS tube power amplifiers as one of the problematics of a wide band Cyclotron RF system.

In the large family of particle accelerators and in the relatively small environment of the wideband cyclic accelerators, the high-power RF Systems were mostly based on the vacuum tube
technologies up to a couple of decades ago. Unfortunately, some alarm bells about the tube market
prospective, relative to the low bandwidth of the cyclotron radiofrequencies, appeared quite clearly
about ten years ago. The cost of some specific tetrodes increased, and their availability decreased.
The two phenomena were counterbalanced by the parallel growth of a very efficient families of
power semiconductors in the low frequency range. Frequency range large enough to easily cover
the cyclotron RF bandwidth. For example, one tetrode, first stage of our RF power amplifier was considered obsolete, and we successfully replaced it with an SSA stage (1-2 kW 15-50 MHz) developed in-house
The undeniable advantages of this choice convinced us to develop a new broadband SSA. A prototype is under study, and a first preliminary conceptual design is in progress. The architecture is developed as a “mosaic”, a series of blocks, called tèssere. A single tèssera* should produce a power of about 5 kW. The composition of several blocks can increase the final power a lot, making the system scalable. The prototype under study is a sort of demonstrator of this scaling model. A final power of 20 kW CW in the range of 10-90 MHz in a space of 10-12 Unit Rack (RF part + power supply) will be our goal.

Speaker: Antonio Caruso (Istituto Nazionale di Fisica Nucleare)

15:50 Status Update on Cyclotron Development and RFQ-Based Injection for the IsoDAR Experiment

The IsoDAR experiment aims to deliver a high-intensity neutrino source for precision measurements in neutrino physics. Central to this effort is the development of a compact, high-current cyclotron capable of accelerating H₂⁺ ions to 60 MeV/amu. This presentation provides a status update on the cyclotron’s development, covering key aspects of its radiofrequency (RF) systems, magnetic configuration and mechanical design.
A major innovation in the IsoDAR injector is the implementation of a novel Radio Frequency Quadrupole (RFQ) inserted into the cyclotron for direct axial injection. We also present the latest details on a smaller cyclotron, designed to match as closely as possible the magnetic and electric fields of the larger cy- clotron, up to 1.5 MeV/amu. This smaller cyclotron will be used to test and validate the injection system and first turns of acceleration. The presentation will conclude with an outlook on upcoming integration tests and commissioning plans.

Speaker: Erik van der Kraaij (Ion Beam Applications (Belgium))

16:10 Development of a α-beam for 211At production at iThemba LABS

South Africa has a proud history of radionuclide production dating back to the 1960s. Since those pioneering years, several improvements and additions have been made to the accelerator infrastructure in the country to exploit this advantage. In recent years an isotope, astatine-211, has emerged as a promising candidate for α-particle therapy of cancers. As a result of this interest, 211At has been identified as one of the radionuclides for development. iThemba LABS is one of about 30 cyclotrons in the world that have the beam characteristics required to produce this isotope. Despite the potential advantages of 211At for targeted α-particle therapy, its application for this purpose is constrained by its limited availability. The most commonly used production method is via the 209Bi(α,2n)211At reaction which utilises bismuth as the target and straightforward cyclotron irradiation methodology. The most significant impediment to the availability of 211At availability is the need for an accelerator capable of generating ≥28 MeV α-particles with sufficient beam intensities to make clinically significant levels of 211At. To this end the biggest challenge faced thus far at iThemba LABS has been extracting enough beam intensity out of the injector cyclotron. With this contribution we will report on the preliminary results of the development to produce α-beam. This discussion will focus on challenges with beam transmission, target development and chemistry.

Speaker: Moenir Sakieldien (iThemba LABS)

16:30 → 18:30 Tuesday Poster Session: TUP

16:30 Optimizing Magnet of IRANCYC-10 Cyclotron: Matrix Modeling vs. Experimental Shimming

This paper presents preliminary steps for the shimming of IRANCYC-10 cyclotron magnet. Shimming, as a crucial step in magnet fabrication, significantly contributes to improving particle acceleration quality, beam stability, and the precision of output energy. Since some shimming procedures—such as pole edge trimming—are irreversible, they require a high degree of accuracy. In this study, the required adjustments for magnetic field corrections are predicted using a matrix method based on mathematical modeling, alongside an experimental approach. A comprehensive comparison of these two methods is provided, highlighting their respective limitations and advantages. The findings of this research offer valuable guidance for optimizing and designing future AVF cyclotron magnets, contributing to their improved performance.

Speaker: Prof. Hossein Afarideh (Amirkabir University of Technology)

16:50 Extension of COLUMBUS Cyclotron Experiments to Helium Ions

In this study, we investigated the feasibility of accelerating helium ions with the COLUMBUS educational cyclotron, which until now had been operated exclusively with hydrogen ions. The primary questions addressed were whether helium ions can be successfully accelerated under the existing experimental conditions, and whether He-3 ions can be detected in the beam.
These questions were first analyzed theoretically, and the resulting insights guided a series of dedicated experiments. The measurements confirmed the acceleration of all four ion species, including the rare He-3 isotope. This achievement demonstrates both the technical feasibility and the pedagogical potential of extending the COLUMBUS program to helium, thereby broadening the scope of student experiments and future workshops.

Speaker: Christian Wolf (Hochschule für Angewandte Wissenschaften Coburg)

17:10 EXTRACTION AND MAGNET DESIGN OF LB-30TP CYCLOTRON

Sichuan Longevous Beamtech is currently developing a tri-particle cyclotron LB-30TP. The LB-30TP cyclotron is designed to be able to accelerate protons(H-) between 13 and 35MeV, deuterons(D-) between 6.5 and 17.5MeV, and alpha particles(He2+) up to 30MeV.
To compensate the difference of relativistic effects between H- and D- beams, two sets of tuning coils are winded around each pole base, while the isochronization of H- beams is achieved by machining of a removable pole edge on one side of each pole. The magnetic pole is designed to be slightly spiral to enhance the axial focusing force, and it also will alleviate the influence of fringe field on the ions that are extracted from different radii on the other side of the pole. The proton and deuteron beams are extracted from the cyclotron by stripping foils, while the alpha particle beams are obstructed by a bismuth target inside the cyclotron for producing At-211.

Speaker: ZHEN SHEN (Sichuan Longevous Beamtech Co., Ltd)

17:30 Design of the 18MeV Injection Line System

This paper presents a comprehensive design study of the H⁻ injection line system for an 18 MeV compact high-current cyclotron. The injection line system, with a total length of 1310 mm, employs a configuration incorporating dual solenoids for transverse focusing and a buncher for longitudinal bunching. Beam transport design and space charge effect simulations were performed using specialized beam optics calculation software.Comparative analysis of buncher performance at 300 V and 500 V led to the selection of 500 V as the optimal operating voltage for longitudinal bunching. The influence of space charge effects at different beam currents (1mA, 3mA, 6mA) on beam envelope was systematically investigated under fixed solenoid strengths. Results demonstrate that while space charge effects significantly affect beam envelope, the 6mA condition remains within design specifications. Beam envelope matching across different space charge conditions was achieved by adjusting solenoid currents, resulting in a maximum envelope below 40 mm and an exit envelope under 20 mm. The normalized emittance after envelope matching reached maximum values of only 0.27365 mm·mrad and 0.27616 mm·mrad in the x and y directions, respectively, at 6mA operation. The optical system can maintain compact beam envelopes throughout transmission while ensuring proper focusing at the line exit. All results fully comply with initial design requirements, providing a reliable foundation for engineering implementation.

Speaker: 毅 杨 (China Institute of Atomic Energy)

17:30 Half-frequency buncher upgrade for SFC cyclotron

To increase the beam transmission efficiency, a new buncher has been installed on the injection line of the HIRFL injector cyclotron SFC. This new buncher uses saw-tooth RF waveform with an effective voltage of up to 2.54 kV and operates at half of the SFC cyclotron RF frequency. With this half-frequency matching mode, we achieve 100% theoretical longitudinal matching between the injector SFC (H=1) and the main cyclotron SSC (H=2). As a result, the beam transmission efficiency has doubled compared to the original full-frequency mode.

Speaker: Xiaoping Sha (Institute of Modern Physics)

17:30 Parameterization of a Cylindrically Symmetric Magnetic Inflector

A cylindrically symmetric magnetic inflector is a promising approach for high energy axial beam injection into cyclotrons. In our previous study, a conceptual design for an H2+ cyclotron demonstrated the feasibility of such an inflector. In this work, we derive parameterization formulas to optimize the inflector field and discuss the injection conditions under different field configurations. Furthermore, we propose a two stage magnetic inflector for cyclotron injection. The required magnetic field of the 2 stage inflector can be naturally generated within the injection hole of the main magnet.

Speaker: lige zhang (TRIUMF)

17:30 Particle Cyclotron Remote Monitoring System

As a high-end scientific research instrument, the stability, reliability, and safe operation of a particle cyclotron accelerator are crucial. Traditional on-site control methods limit the flexibility of researchers, especially when timely responses to equipment status or long-term experiments are required. This study aims to design and implement a remote monitoring system for the particle cyclotron accelerator, aiming to overcome geographical constraints and provide researchers with the ability to safely, in real time, and efficiently monitor and intervene in the key parameters of the cyclotron accelerator.

Speaker: 慧媛 刘 (China Institute of Atomic Energy)

17:30 Physics design of a compact cyclotron for isotope production

Nowadays, there are almost 5 million new patients every year who get cancer in China. However isotope drugs are not enough according to this large numbers of patients. A compact cyclotron with 16-MeV proton is designed for current tough situation to product isotopes.
The diameter of the core part of this compact cyclotron is less than 60 cm. Physics simulation has been done by the CODE CYCLONE. With adjust extraction, a reasonable current of 100 um can be got by this machine. This paper will report the study in detail.

Speaker: Guohui Wei (Institute of Energy, Hefei Comprehensive National Science Center)

17:30 Research on the Preparation Process of Tantalum-Based Electrodeposited Nickel Targets for Accelerator-Based Production of ⁶⁴Cu

In order to enhance the coating quality of tantalum-based electroplated nickel targets for the production of ⁶⁴Cu radionuclides, and to address issues such as thin and easily detachable nickel coatings in conventional targets, this study systematically investigated the pretreatment processes of tantalum substrates, the composition of the plating bath, and electroplating parameters. The effects of pretreatment methods, pH of the plating bath, surfactant concentration, current density, temperature, and agitation rate on the quality of the nickel coating were examined. The fabricated targets were subsequently characterized through metallographic examination, drop tests, and thermal shock experiments. Results demonstrated that under ambient temperature conditions, by adjusting the plating bath pH to 9.80 with ammonia, maintaining a sodium dodecyl sulfate concentration of 15 mg/L, applying a current density of 3 mA/cm², an agitation rate of 200 r/min, and an electroplating duration of 2 hours, a high-quality tantalum-based electroplated nickel target suitable for accelerator-based ⁶⁴Cu production was achieved. The resulting coating exhibited a thickness of 20.87 mg/cm², with excellent uniformity, adhesion, and thermal stability. Additionally, the utilization efficiency of Ni²⁺ in the plating bath reached 60%.

Speaker: Mr Yu Wang (China Institute of Atomic Energy)

17:30 RF Design, Fabrication, Commissioning, and Testing of a Significant-beam-loading Buncher with Synthesized Fundamental and Third-Harmonic Operation

China Institute of Atomic Energy is upgrading the injection line of the 100MeV high current compact H- cyclotron (CYCIAE-100) with the aim of extracting mA level beam from the cyclotron to meet growing scientific research and commercial application demands, ultimately aiming to establish the world's highest beam power cyclotron facility. The buncher upgrade represents a critical component of this project. The buncher can effectively enhance the beam current within the acceptance phase of the cyclotron and optimize beam performance parameters. The newly developed buncher system employs a bunching voltage synthesized from the fundamental and third harmonics, for which a compact cavity matching circuit supporting both harmonics was specifically designed. The cavity adopts a λ/4 coaxial transmission line structure, was modeled and optimized for key parameters such as frequency and Q-factor using CST software, and the cavity was folded to accommodate the compact layout of the injection line. The cavity matching circuit and buncher have now completed cold testing and highpower testing, have been successfully installed in the injection line, and have undergone online testing under low-beam-current conditions. The results demonstrate a bunching gain of 2.2 achieved at an ion source extraction current of 1.4 mA, providing preliminary verification of the buncher's proper operation.

Speaker: xinyu li (China Institute of Atomic Energy)

17:30 Study and Survey on the Beam Spot Shape Invariance during Gantry Rotation

Particle therapy gantries are essential for modern radiation therapy, requiring precise beam spot control to ensure dose delivery accuracy during multi-angle irradiation. However, gantry rotation alters the relative positions of optical components, affecting beam spot characteristics. Current solutions each offer distinct advantages under different system conditions. A unified theoretical analysis is imperative to reconcile these approaches, elucidate their intrinsic connections, and ultimately enrich the design paradigm for rotation-invariant systems.
This study not only integrates existing approaches but also introduced A novel constraint (Mx=My) for the gantry transfer matrix. It ensures beam spot invariance without needing symmetric input beams or extra rotators. This constraint offers a versatile and cost-effective solution for gantry design. Simulations validate its effectiveness in maintaining stable beam spots across all rotation angles, even with asymmetric emittances. Importantly, the proposed framework integrates seamlessly with existing techniques, such as sigma matching, thereby enhancing the overall robustness and adaptability of gantry systems.
This work proposes a unified design framework for rotation-invariant beamline systems in particle therapy, providing theoretical foundations for future system optimization.

Speaker: yandong zhu (Sichuan University)

17:30 Study on the Injection Line for a 30MeV High-Current Cyclotron

The China Institute of Atomic Energy is developing a 30 MeV high-current cyclotron. To meet the injection requirements of the accelerator, this paper presents the injection line design and particle tracking simulation calculations. The injection line employs a combination of electromagnetic lenses for beam focusing. The overall injection field spans 1.19 m and consists of electrostatic lenses, a collimator, and a solenoid. The beam current reaches 6 mA, with a final RMS beam size of 5.39 mm, meeting the accelerator's injection requirements.

Speaker: Mr Tianhao Cui (China Institute of Atomic Energy)

17:50 the design of the neutron exit of the neutron source based on the cyclotron by simulation to improve the thermal neutron flux

A neutron source based on the 18 MeV cyclotron is designed for thermal neutron imagine. A groove is usually designed at the thermal neutron exit to improve the thermal neutron flux. To further improve the thermal neutron flux and decrease the gamma in the neutron beam, some cerium sticks are placed in the neutron port. Because the thermal neutron reaction cross-section in cerium is smaller than this in the moderator, and the gamma reaction cross-section in cerium is larger than this in the moderator. Neutrons tend to propagate preferentially along the cerium sticks, thereby enhancing the collimation of the emitted thermal neutron beam. Simultaneously, the gamma in the thermal neutron beam is effectively reduced.
A thermal neutron exit is designed as a circle with the 10 cm-diameter, incorporating cerium sticks with a radius of 0.2 mm spaced at 1 cm intervals. By simulation, when the cerium sticks placed in the exit, the thermal neutron flux at 10 meters from the source increased from 5.12×10-11 n/cm2/proton to 5.81×10-11 n/cm2/proton, while the gamma flux decreased from 8.03×10-11 n/cm2/proton to 6.99×10-11 n/cm2/proton .

Speaker: Ye Zhu (China Institute of Atomic Energy)

18:10 A Cyclotron-based BNCT-TPS design

Boron neutron capture therapy (BNCT) is a binary targeted radiotherapy technique that exploits the high neutron-capture cross-section of Boron-10. The treatment planning system (TPS) is the essential component of the BNCT system used to make treatment plans for patients, which can simulate the treatment process, adjust the parameters in the irradiation process and calculate the dose in the patient. With the development of accelerator technology, accelerator-based BNCT has entered the stage of rapid development around the world. However, cyclotron-based BNCT and its’ TPS in China exist flaws, significantly impeding the progress of BNCT clinical applications. To address this issue, an independently developed BNCT-TPS has been designed based on 18 MeV high-intensity proton cyclotron in CIAE. The system developed a range of tools and features including medical image processing, 3D data reconstruction, tumor target delineation, particle transport simulation (using MCNP as Monte Carlo engine), dose distribution output and optimization. It has been built to be a user-friendly interface and expected to be updated for clinical practice.

Speaker: Yaozhu Chen (China Institute of Atomic Energy)

18:10 A Spatio-Temporal and Management-Based Multi-Dimensional Integrated Safety Management System for Cyclotron Operation and Experiments

Traditional safety management models for cyclotron operation and experiments, which address potential risks such as radiation safety, personal safety, and equipment safety, suffer from issues like information silos, insufficient dynamic response, and regulatory blind spots. This paper proposes and preliminarily designs a safety management system architecture based on "spatio-temporal full coverage and multi-dimensional collaborative management." It aims to establish a proactive and humanized safety management system that achieves comprehensive multi-dimensional coverage through three aspects: temporal processization, spatial zonation, and management systematization, thereby comprehensively enhancing safety assurance levels and emergency response capabilities. This design achieves seamless safety monitoring of the cyclotron facility across both time and physical space. It enables dynamic perception of the safety situation, facilitating a shift from reliance on "human defense" and "technical defense" towards a comprehensive, systematic, and ecological approach.

Speaker: 勇 章 (Hefei Institutes of Physical Science)

18:10 Automated Separation and Purification of 68Ge from Cyclotron-irradiated Ga-Ni Alloy Targets

1. Introduction.
   Germanium-68 (68Ge,T1/2=270.9 d) serves as a crucial precursor for the 68Ge/68Ga generator, which provides radionuclide gallium-68 (68Ga, T1/2=67.7 min). The present study aimed to develop an efficient and automated methodology for the separation and purification of 68Ge from the irradiated Ga-Ni alloy targets.
2. Method
   The Ga-Ni alloy targets were dissolved in a mixture of sulfuric acid and hydrogen peroxide at 95℃using an automatic dissolution apparatus. Subsequently, the conditions for purifying germanium via a double-column approach (Hydroxamate and Sephadex G 25 resin) were optimized, and the process validated through radiochemical separation experiments for 68Ge.
3. Results & Conclusion.
   As shown in Figure 1, the hydroxamate resin (Column-A) removed impurities including Ga, Ni, and Zn; the Sephadex G-25 resin (Column-B) then eliminated Nb and Au. The radiochemical separation experiments of 68Ge confirmed a separation recovery rate exceeded 90%. The 68Ge product exhibited a radionuclide purity greater than 99.9% with all elemental impurity levels below 1.5 ppm (Table 1). In conclusion, the established automated double-column separation process proves to be stable and efficient, offering a reliable technical foundation for the large-scale production of high-quality 68Ge.

Speaker: FEI DUAN (High-Tech Atomic Co., Ltd.)

18:10 Beam Dynamics Analysis of the Axial Injection System for the CIM30 Cyclotron

An axial injection system has been developed for the CIM30 cyclotron, which is designed to accelerate α-particles up to 30 MeV for medical isotope production of At-211. This system transports a 50–60 keV α-beam from an external ion source into the cyclotron center. Both transverse and longitudinal focusing are applied to ensure high beam extraction efficiency and quality. The injection line consists of dipole magnets, a buncher system, a beam diagnostics system, a vacuum system, Glaser lens, and a spiral inflector. The buncher and the spiral inflector are identified as key components. Their physical design and beam dynamics characteristics are described in detail. Additionally, mechanical and magnetic tolerances of the injection system are analyzed, providing a basis for engineering design.

Speaker: Feng Jiang (Institute of Plasma Physics)

18:10 Conceptual Design of a 70 MeV/u Variable-Energy Superconducting Cyclotron for Multipurpose High-Intensity Applications

Conventional superconducting H₂⁺ cyclotrons are inherently limited in variable energy extraction, as the stripped particles spiral inward, constraining both trajectory control and beam quality. To meet the increasing demand for high-intensity, variable-energy beams across a wide range—particularly for applications in medical isotope production and proton FLASH therapy—this study presents the physics design and magnet simulation of a novel 15–70 MeV/u variable-energy, multi-particle superconducting cyclotron. The proposed cyclotron is capable of accelerating particles with a charge-to-mass ratio of 1:2, such as H₂⁺ and He²⁺, with intense proton beams obtained via H₂⁺ stripping. To address the long-standing challenge of multi-turn extraction for H₂⁺ at low energies, an alternating-sign field configuration was introduced to enable rapid extraction. Based on a detailed particle orbit model, the key magnetic parameters were optimized, yielding a hill field of 3.6 T, a valley reverse field of 0.6 T, and a sector angle of 36–40°, which also provides sufficient space for RF cavity installation. Finite-element simulations further demonstrated the feasibility of a compact superconducting magnet system, where coils are wound directly around the pole structure. This design enhances axial focusing while maintaining compactness. Static beam dynamics calculations confirm that the transverse oscillation frequency remains below 1.9, effectively avoiding low-order resonance risks.

Speaker: Wei Fu (China Institute of Atomic Energy)

18:10 Control System Development for Ultra-compact Multi-particle SC Cyclotron

The China Institute of Atomic Energy is developing an ultra-compact multi-particle superconducting cyclotron, which can provide two different ions, including a particle and H_2^+ with corresponding energies. To ensure convenient operation and stabilize the beam current, a PLC-based control system with comprehensive interlock protection has been developed. This paper presents the design of a PLC-based control system. The system utilizes a distributed industrial network architecture, enabling supervisory control of key subsystems, including the superconducting magnet, radio frequency system, and ion source. It allows real-time monitoring and precise control, integrating functions such as interlock protection, data acquisition, remote operation, and fault diagnosis to ensure stable and reliable cyclotron operation. An innovative PLC-based automated protection system for low-temperature superconducting coils has been developed to prevent quenching. It’s believed that such a system will significantly improve reliability and maintainability of the superconducting cyclotron. In this paper, a multi-mode operation design will be reported, which combines automation with manual intervention, offering high scalability and fault tolerance. The development of a generalized, intelligent PLC control program will also be reported, which can provide reliable control of the ultra-compact multi-particle cyclotron for various applications, including research on biological effects.

Speaker: dongxu ran (China Institute of Atomic Energy, Chengdu Cyclotron Science and Technology Co., LTD)

18:10 Cyclone® IKON : From commissioning to operation

At the CYC2022 conference, IBA presented its new 30 MeV proton accelerator. The first installation of this Cyclone® IKON, with four beam transmission lines and a beam energy of 30 down to 13 MeV, has now successfully been commissioned and is running at a customer site.
In this presentation we will go into the details of the accelerator’s performance, from its injection to its transmission, plus intensity on targets. With the accelerator fully operational, we will also present a comparison of the latest results with the design and commissioning simulations.

Speaker: Erik van der Kraaij (Ion Beam Applications (Belgium))

18:10 Design and analysis of a compact single-stage cavity combiner for the 20kW solid state amplifier under vacuum

Focusing on high-power radio-frequency systems for ultra-lightweight high-temperature superconducting cyclotrons in special environments, we aim to make breakthroughs in key technologies that restrict the improvement of radio-frequency system reliability for highly automated cyclotrons. Research has been conducted on direct power combining technology and dynamic matching adjustment for solid-state power amplifiers at the 20-kW level. A dynamically tunable single-stage cavity direct power combiner based on a TEM cavity has been designed. Radio-frequency power signal flow analysis has been performed for a system with 24 inputs and one output. Research has also been conducted on the impact of up to three module failures at arbitrary positions on the total production of the power source under different power combining circuit topologies, as well as corresponding compensation methods. It is expected to achieve iterative breakthroughs in key technologies such as ultra-lightweight high-power radio-frequency cavity direct synthesis and adaptive power amplification circuit topology reconfiguration for solid-state power sources. This paper reports an adaptive, highly redundant, and lightweight solid-state radio-frequency power amplifier system designed for space applications.

Speaker: zhuoheng liu (China Institute of Atomic Energy, Chengdu Cyclotron Science and Technology Co., LTD)

18:10 Design and fabrication of a large area multi-strip ionization chamber for proton therapy

Focusing on the high precision dose distribution monitoring in the spot scan beam delivery system of proton therapy, we design and fabricate a high-precision ionization chamber with multiple strip electrodes, ensuring a stable gain from the ionized pair. Based on advanced laser etching technology, using aluminum-plated polyimide film as the electrode material, we investigated multiple fabrication parameters to produce high-precision, flexible strip PCBs. Using these flexible PCBs as central detection parts, we designed a large-area parallel plate ionization chamber with integrated dose and position monitoring. The reported ionization chamber has a sensitive area of 256 mm by 256 mm, comprising 256 channels in the X-direction and 256 channels in the Y-direction, along with two mutually verifiable integral plane electrodes. The ultra-thin film electrodes and window materials allow for virtually non-invasive ion beam measurements with a water-equivalent thickness of less than 0.3 mm. This ionizing chamber can be integrated into the nozzle of a proton therapy system to measure beam spot position in real-time. It also provides precise dose distribution information and can be integrated into quality assurance systems to make diagnostics at the iso-center. The design, fabrication results of the large-area domestic ionization chamber will be reported in this paper.

Speaker: xiaoqing ren (China Institute of Atomic Energy, Chengdu Cyclotron Science and Technology Co., LTD)

18:10 Design and Implementation of a Wire Scanning System for CYCIAE-18 HIGH CURRENT PROTON CYCLOTRON

The China Institute of Atomic Energy (CIAE) has de-veloped a multipurpose, high-intensity 18 MeV/1 mA cyclotron (CYCIAE-18) for Boron Neutron Capture Therapy (BNCT) applications and neutron imaging studies. The degree of beam homogenisation directly affects the uniformity of the dose distribution and the imaging contrast. In order to confirm that the pre-experimental condi-tions have been met, it is necessary to develop a wire-scanning system for beam diagnostics, which is used to measure the beam cross-section and calculate the degree of homogenisation. This system enables the synchronous, high-precision acquisition of position and current signals and uses a Python-based host computer interface for re-mote control of the wire-scanning device. Meanwhile, its modular design integrates each signal processing unit into a compact chassis, effectively improving the system's maintainability and expandability. Testing has shown that the system can measure the beam cross-section in 1–2 seconds and achieve a homogenisation measurement result of >90% between peaks. The system has achieved cross-section measurement of the CYCIAE-18 beam, providing a key diagnostic tool for beam commissioning, optimisation, and operation.

Speaker: xianping li (China Institute of Atomic Energy)

18:10 Design and Principle Analysis of Automated Multi-Specification Target Pneumatic Rabbit System for Isotope Production Line

In medical isotope production, target materials for dif-ferent isotopes exhibit significantly different physical properties. To improve nuclear reaction yield and effi-ciency, target structures of various specifications are required to produce different radioisotopes. However, multi-specification targets hinder automated production and increase on-site operation time. To reduce personnel radiation exposure risk in high-radiation environments, enhance rabbit system automation, and improve target specification universality, this study designs a complete automated multi-specification pneumatic rabbit system. A dual-specification target rabbit box is designed using a multi-gear buckle device. Segmented pneumatic trans-mission simulations verify system design rationality, and pipeline parameters and control processes are determined. The system enables bidirectional pneumatic transmis-sion, precise positioning, and automated operation, providing a new solution for safe and efficient medical radionuclide production.

Speaker: Ms Jiajing Bao (China Institute of Atomic Energy)

18:10 Design and Test of the Phase Probe for CYCIAE230 superconducting cyclotron

Ever since the first non-classical isochronous cyclotron was invented in 1956, the stability of the isochronism of this kind of accelerator has been pursued for decades. For the CYCIAE-230 superconducting cyclotron, the matching between the RF frequency and the magnet field is even more challenging. A dedicated 2nd harmonic resonator has been designed, manufactured, and installed on the beamline to track the phase drift of the cyclotron-extracted beam. Front-end electronics and embedded software have been implemented to detect and broadcast the beam phase via a local Ethernet connection. A dedicated software has been developed to trace the phase error and constantly regulate the frequency of the master oscillator of the cyclotron in a predefined frequency range. The same software also takes supervisory control of the excitation current of the superconducting coil and the temperature of the magnet. Online tests have been conducted using the cyclotron beam and the phase probe system. Preliminary results indicate that the resonator has a good signal-to-noise ratio and can detect magnetic field drift in the order of 10^-7. In the meantime, the system can also be used as a non-invasive beam current detector, providing valuable information to the beam current regulation system. This paper reviews the design of the phase probe, electronics, and software, along with preliminary test results.

Speaker: Tianyi Jiang (China Institute of Atomic Energy)

18:10 Design of a set of multi-use field measurement system and its control algorithm for Cyclotron beamline magnets

Beamline magnets are essential parts of an accelerator system in order to ensure final beam quality on the target. Thus it is necessary to conduct magnetic field measurement and shimming to ensure that ever magnet has sufficient field accuracy. CIAE is vigorously promoting the industrialization of cyclotrons and the promotion of design capabilities for other types of particle accelerator. In order to conform with such tendency, a new set of magnetic field measurement system is designed, which can be easily transferred between point measurement mode and rotation measurement mode. The system consists four axes of motion: 3 translational axis following Cartesian System and 1 rotation axis following axial direction, and the control system is designed to be able to conduct field measurement automatically. For accuracy, field measurement system uses high-precision hall probe and moves in go-stop mode when run in point measurement mode; when it runs in rotation measurement, the system uses induction coil and switch to external trigger mode, allowing users to gain field reading while the probe is rotating.

Speaker: Xinyu Chen (China Institute of Atomic Energy)

18:10 Design of Radiation Safety System for the Huludao Base Cyclotron Accelerator Facility

Abstract: In Huludao a new base for the development center of the cyclotron is about to be built by China Institute of Atomic Energy. Two cyclotrons will be built in this facility. To prevent received overdose of radiation during the operation and commissioning, we designed a set of radiation monitoring and safety system for the machine. This system serves to protect the operating personnel and the public from accidental ionizing radiation damage. To fulfil the safety requirements, a dose monitoring and safety interlock system based on a Programmable Logic Controller (PLC) has been developed. This system promise that no operator stays in the control zone during operation and beam can’t be delivered to the area under maintains. This paper elaborates in detail on the design structure of this system and the control logic. Additionally, it describes the expected effects when the system is operated in the cyclotron research and development center at the Huludao Base.

Speaker: 媚娆 孙 (China Institute of Atomic Energy)

18:10 Design of the Desktop Hard X-ray Source Measurement and Control System

To bridge the gap between conventional X-ray tubes and large-scale X-ray generation facilities, we have developed a Desktop Hard X-ray Source. This device provides higher X-ray intensity compared with traditional X-ray tubes while maintaining advantages of compactness, low cost, and ease of operation. The device consists of three main components: an injector, a beam transport line, and a storage ring. In this system, the electron beam generated by the injector is resonantly injected into the storage ring, where it circulates at high speed. During circulation, the electron beam repeatedly collides with a metallic micro-target installed inside the vacuum chamber, thereby generating X-rays. To achieve a more compact configuration while ensuring improved beam quality, an electron cyclotron accelerator is employed as the injector. This accelerator offers benefits such as small size and high microwave power efficiency. To ensure precise and stable operation of the device, a dedicated measurement and control system has been designed. The software framework of this system is built on Debian 12 and EPICS 7, integrating all device control and data processing into EPICS IOCs and establishing interconnections among relevant PVs. An OPI has been developed based on Phoebus to support system operation. In addition, machine learning techniques have been explored for integration into the control system to further enhance the intelligence and accuracy of control strategies.

Speaker: Mr Zhengyu Wei (National Synchrotron Radiation Laboratory, University of Science and Technology of China)

18:10 Design of Tuning Loop for Cyclotron RF System Based on FPGA with FFT/CORDIC Algorithm

Abstract
The Low-Level Radio Frequency (LLRF) system is crucial for amplitude and phase control in modern parti-cle accelerators. Traditional amplitude and phase de-modulation methods often require the sampling frequen-cy to be multiple of the high-frequency signal, leading to limited general applicability. To address this issue, this paper proposes a generic tuning control method, imple-mented on an FPGA platform, which is based on FFT (Fast Fourier Transform)/CORDIC (Coordinate Rotation Digital Computer) demodulation and features independ-ent control functionality. This scheme directly samples the cavity and transmission line signals, employs FFT/CORDIC for amplitude and phase demodulation to derive the signal phase difference, and utilizes a PID algorithm to control a stepper motor for fine-tuning the cavity capacitance, thereby achieving resonant frequency tracking. To balance computational resource consump-tion and latency, an FPGA-based 2048-point FFT opera-tional structure and a CORDIC module with 16 iterations were designed. Simulations demonstrate that the phase measurement error of the proposed method is less than 0.06°, meeting the tuning precision requirements for accelerator cavities.

Speaker: Jiayi Zhang (China Institute of Atomic Energy)

18:10 Design Study of the Main Magnet for a 100 MeV Spiral-Sector Cyclotron at CIAE

The development of a 100 MeV Spiral-Sector cyclotron, which is capable of extracting a beam with a rated power exceeding 50 kW, is in progress at The China Institute of Atomic Energy. Such a machine is designed for the production of medical radioisotopes for nuclear medicine. The basic parameters of the isochronous cyclotron magnet and its characteristics are described. An isochronous magnetic field was achieved by adopting the upper surface shimming scheme. The spiral angle was adjusted to control the vertical betatron tunes and avoid potentially harmful resonances during acceleration. We performed iterative magnetic field optimization with OPERA-3D, followed by detailed beam dynamics simulations and Lorentz stripping loss analysis. This process ultimately improved the beam acceleration efficiency. Guided by simulated electromagnetic deformation data, the magnet structure was further optimized for weight reduction through an analysis of its stress distribution and magnetization characteristics.

Speaker: JinRong Lu (China Institute of Atomic Energy)

18:10 Development of a Distributed Intelligent Control System for compact Cyclotron

Modern compact cyclotrons have multiple system components and are used for isotope research, neutron imaging and BNCT. All these applications demand that the cyclotron possesses high reliability. Focusing on the series of compact high-current cyclotrons of the China Institute of Atomic Energy, a control system architecture is constructed in this paper, which effectively improves the stability and efficiency of the control system. A standard three-layer distributed control architecture has been designed for multiple cyclotron systems. Based on functional division, a multi-threaded approach was im-plemented at the top layer of the control system to han-dle different tasks, effectively enhancing the accelerator's operational efficiency. This paper provides a stable and scalable distributed control solution for the compact cyclotron, which provides a reliable guarantee for im-proving the operation of the accelerator, and more intel-ligent control technology will be completed based on this system in the future.

Speaker: Mr YunLong Li (China Institute of Atomic Energy)

18:10 Development of the Multi-Channel Beam Diagnostics Electronics for Cyclotrons

To address the beam diagnostics requirements of multiple cyclotrons at China Institute of Atomic Energy (CIAE), a multi-channel digital beam diagnostics electronics system based on current-to-voltage (IV) conversion was developed. The IV conversion circuit integrates high-precision operational amplifiers with ultra-low bias current and low-temperature-drift resistors. The system implements a hybrid filtering architecture: analog filters and digital filters. The analog filters include the first-order RC filter and the second-order MFB low-pass filter, and the digital filters include the FIR filter, median filter, and MAF filter. Xilinx Artix-7 series FPGA(XC7A100T-2FGG484I) is used as the main controller and an 8-channel 18-bit resolution ADC(AD7606C-18) is used to realize analog-to-digital conversion. UDP protocol is selected as the communication protocol between the electronic system and the host PC or PLCs. Test results show that the max 0.5% relative error can be reached when the beam current ranges from 100 pA to 20 mA, with linearity R² > 0.999999 for all channels. The system has been validated through long-term operation on CIAE’s high-current accelerators (e.g., BNCT and neutron imaging accelerators, with the 16-channel electronics) and low-current accelerators (e.g., 16 MeV and 9.5 MeV cyclotrons, with the 8-channel electronics).

Speaker: Peng Huang (China Institute of Atomic Energy)

18:10 Development of the Multi-Channel Beam Diagnostics Electronics for Cyclotrons

Abstract:
To address the beam diagnostics requirements of multiple cyclotrons at the China Institute of Atomic Energy (CIAE), a multi-channel digital beam diagnostics electronics system based on current-to-voltage (I/V) conversion was developed. The I/V conversion circuit integrates high-precision operational amplifiers featuring ultra-low bias current and low-temperature-drift resistors. The system implements a hybrid filtering architecture: combining analog and digital filters. The analog filters comprise a first-order RC filter and a second-order MFB low-pass filter, while the digital filters consist of FIR, median, and MAF filters. The Xilinx Artix-7 series FPGA(XC7A100T-2FGG484I) serves as the main controller and an 8-channel, 18-bit ADC is employed for signal digitization. The User Datagram Protocol (UDP) is adopted for communication between the electronics system and the host PC or PLCs. Test results show that a maximum relative error of 0.5% is achieved when the beam current ranges from 100 pA to 20 mA, with a linearity coefficient (R²) greater than 0.999999 for all channels. The system has been validated through long-term operation on CIAE’s high-current accelerators (e.g., BNCT and neutron-imaging accelerators equipped with the 16-channel electronics) and low-current accelerators (e.g., 16 MeV and 9.5 MeV cyclotrons equipped with the 8-channel electronics).

18:10 High Resolution Electronics for Radial Probe of Superconducting Cyclotron for Proton Therapy

It is inevitable to carry out beam diagnostics inside the superconducting cyclotron used for proton therapy at the application site. Radial probe plays an essential role in the field of beam diagnostics for SC cyclotrons. Years of efforts have been put forward by a group in the China Institute of Atomic Energy, focusing on advancing the beam diagnostics probe and readout electronics for the R-Probe system of the CYCIAE230 SC cyclotron. The EM interference inside the compact cyclotron poses a significant challenge for precise beam diagnostics. For example, when the R-Probe is moving along the radial path, the alternating high voltage from the RF system and the strong magnetic field generate greater noise than the signal itself. Care has been taken with the shielding and grounding design of the new radial probe used in the large radius. A replaceable scintillator-based probe head is also included for the beam diagnostics in the center region. The electronics design utilize a logarithmic amplifier, which yields a dynamic range of 140dBV, providing greater flexibility compared to the feedback IV ammeter. Fast ADC, as well as ZYNQ SOC, is used to reduce the noise to an acceptable level further. Besides, a magnetically friendly, lens group and a CMOS camera are developed and integrated for the scintillator-based probe head. The design of the new R-Probe for CYCIAE230 S.C. cyclotron will be reviewed in this paper, together with the preliminary test results.

Speaker: fu zheng (China Institute of Atomic Energy, Chengdu Cyclotron Science and Technology Co., LTD)

18:10 High-Frequency Air-Core Transformer Design

Compact cyclotrons need kilovolt Radiofrequency in the MHz range, yet product changeovers increasingly demand drives that can retune frequency, amplitude, and duty cycle. We report the design and experimental validation of a high-voltage, low-MHz transformer/matching network tailored for a digitally synthesized, soft-square Class-D driver. The method co-optimizes magnetizing inductance, leakage inductance, and winding capacitance to preserve Zero Voltage Switching and constrain dv/dt under variable frequency (2-4 MHz) and duty cycle. In this paper we provide a CAD layout and calculation and simulations and adjusting properties, resulting in an optimal geometry of the transformer.
These calculations adjusted the range of each property of the transformer in order to work within required range of frequency and voltage. These are material choice, quantification of the coupling k, spacing trade-off, and production of parameters suitable for 2-4 MHz operation and the design of the secondary circuit. This establishes a reproducible path from geometry to circuit model for a high-voltage RF transformer supporting agile RF drives.

Speaker: Sepehr Farid (Coburg University of Applied Sciences)

18:10 Investigation of Negative Hydrogen Ion Beam Profile in the Karaj C30 Cyclotron Using Mylar Foil

The 30 MeV Karaj-C30 cyclotron, developed for medical and industrial radioisotope production at the Karaj Research Institute for Agricultural, Medical, and Industrial Studies, accelerates H- ions to 15–30 MeV and D- ions below 15 MeV. The system features a filament-based negative hydrogen multicusp ion source providing 1–2 mA, an injection line with optical elements, a two-sector electromagnet, and an RF resonator. It was observed that after a period of cyclotron operation, the beam current on the target gradually decreased. Examination revealed beam impingement on optical elements, indicating misalignment. A Mylar foil was used to investigate the beam profile. The recorded beam profile on the foil was analyzed through image processing. It was found that the beam was misaligned with respect to the beam transport line. Further investigation revealed that the ground electrode had undergone corrosion, as the magnets within the puller electrode caused deflection of the ion beam, leading to its collision with the ground electrode. Erosion of the ground electrode generated a radial electric field deflecting the beam. After replacing the ground electrode with an identical, non-corroded electrode, the beam profile was re-evaluated under the same operating conditions, and it was observed that the beam had been successfully realigned with the beam transport line.

Speaker: Keyvan Tabaei (University of Isfahan)

18:10 Magnet System Design and Static Analysis of a Superconducting Ring Cyclotron for Thorium Molten-Salt Energy Amplifiers

Abstract:
Superconducting ring cyclotrons (SRCs) are widely studied as drivers in accelerator-driven systems (ADS) for thorium-based molten-salt energy amplifiers, owing to their capability of delivering high-energy and high-intensity beams. This poster presents the magnet system design of an H₂⁺ superconducting separated-sector cyclotron with an extracted beam energy of 800 MeV/amu for ADS applications.
The required beam quality for this cyclotron is defined according to the operational criteria of the Thorium-Based Molten Salt Reactor System as outlined in a recent study on thorium-based energy amplifiers at the Shanghai Institute of Applied Physics.The main tasks include modeling the magnet system, optimizing the isochronous magnetic field, and performing equilibrium orbit analysis to verify stable beam dynamics.
The results demonstrate that the optimized field configuration can achieve the required isochronous condition with tolerances compatible with ADS operation, providing a solid foundation for further beam dynamics and engineering studies.

Speaker: minggao xia (Shanghai Institute of Applied Physics)

18:10 Numerical validation of theoretical isochronous cyclotron energy limits

In the previous cyclotron conference, an analytical prediction for the energy limit of isochronous cyclotrons was presented. The current paper shows numerical results to validate this model. For this purpose, extensive use is made of a tool that creates artificial isochronous magnetic field maps; a tool that is the subject of another contribution to this conference. A wide range of field maps with varying rotational symmetry numbers, varying flutter profiles and varying sector spiral angles is studied. Besides the energy limits, other optical properties such as the radial and vertical tunes and the stop-band of the 2Nur=N resonance are compared with the analytical predictions. The quality of agreement between theory and simulations is good but, as will be shown in the paper, depends on the amount of flutter in the map.

Speaker: Willem Kleeven (Ion Beam Applications (Belgium))

18:10 Optimizing Magnetic Flux Distribution in MA-Loaded Cavities through Nested Core Architecture for Scaling FFAG Accelerators

Magnetic alloy-loaded RF cavities are critical components in scaling Fixed-Field Alternating Gradient (FFAG) accelerators, enabling ultra-high acceleration gradients and broad frequency operation without tuning. As FFAG accelerators advance toward higher power applications, enhanced cavity performance through improved magnetic core design becomes essential. Current large-scale magnetic cores fabricated from 18-micrometer nanocrystalline ribbons face limitations in shunt impedance for high-power operation. While ultra-thin ribbons (13-micrometer) theoretically offer superior performance through increased permeability and reduced eddy current losses, practical implementation encounters significant challenges including high costs, manufacturing difficulties, and stress sensitivity in large cores. This study proposes a novel nested core architecture utilizing selective ultra-thin ribbon placement in specific radial regions while maintaining conventional thickness materials elsewhere. Through theoretical analysis and simulation, we demonstrate that this approach not only provides cost-effective impedance enhancement but also redistributes magnetic flux density to improve temperature uniformity—critical for high-power FFAG applications. The nested design addresses power scaling challenges while maintaining economic viability, offering a promising solution for next-generation FFAG accelerator systems.

Speaker: Bin Wu (Institute of High Energy Physics)

18:10 Preliminary Study of Beam Orbit Correction and Betatron Tune Characterization in CSNS-FFAG Accelerator

This paper presents beam dynamics studies for the CSNS-FFAG accelerator, designed for 50kW proton beams at 25Hz repetition rate. We report on orbit correction and betatron tune measurement methods developed for this fixed-field alternating gradient machine.

Speaker: Yuwen An (Institute of High Energy Physics)

18:10 Production of high-intensity titanium ion beams by plasma sputtering

The research program of Flerov Laboratory of Nuclear Reactions (JINR) in the synthesis of Super Heavy Elements and in applied research requires the production of intense accelerated beams of solid materials. Constant developments are being made to broaden the range of available beams for physics.
In this paper we report the results of production Ti ion beams by plasma sputtering. The experiments were performed with DECRIS-5M ion source at the Flerov Laboratory of Nuclear Reactions at ECR test bench.

Speaker: Andrei Bondarchenko (Joint Institute for Nuclear Research)

18:10 R&D of Multichannel Readout Electronics for Compact Ion Chambers of Nozzle for Proton Therapy

A superconducting cyclotron-based proton therapy system has been developed at the Chengdu Cyclotron Science and Technology Co., Ltd. (CCST). For a cyclotron-based proton therapy system, the ion chamber at the nozzle is crucial for both the therapy system and the adaptation of the planning system. In practice, to achieve low noise measurement, the existing system is equipped with 256 triaxial cables from the ion chambers to the readout electronics, which brings an extremely high cost and is space-consuming. Distributed multi-channel readout electronics are designed and partially integrated into the ion chamber of the nozzle, thereby increasing the signal-to-noise ratio in detecting the scanning beam spot position. For this purpose, multiple 128-channel Current-to-Digital ADCs are integrated into the ion chamber to digitize the charge and enhance electronic electromagnetic compatibility. The digital readout electronics are based on the ZYNQ 7020 and transmit data via the AXI GPIO bus and the UDP protocol, which meet real-time requirements. Besides that, a low-overhead beam center localization algorithm is designed, which is suitable for embedded electronics. This paper reviews the design of the multichannel readout electronics for compact ion chambers, along with preliminary test results.

Speaker: qingwei han (China Institute of Atomic Energy, Chengdu Cyclotron Science and Technology Co., LTD)

18:10 Research and Design of Ionization Chambers for the Spatial Radiation Effects Analysis Experimental Platform and the Huairou (50 MeV) Proton Cyclotron Facility

To monitor the beam energy and transverse distribution of the 50 MeV proton cyclotron facility in Huairou, a fixed-spacing strip ionization chamber is planned for development. Based on factors affecting the measurement accuracy of flat-panel ionization chambers, Monte Carlo simulation software such as Geant4 and Srim was employed to calculate parameters including energy deposition and particle transmission efficiency within the flat-panel ionization chamber under various influencing factors. Through analysis, the final ionization chamber structure, material composition, and working gas selection were determined. Simulation calculations confirmed the final strip ionization chamber design: a 50μm-thick Mylar film with double-sided aluminum coating serves as the high-voltage electrode, while a 150μm-thick flexible PCB functions as the collecting electrode. The spacing between the high-voltage electrode and collecting electrode is 3mm, with air as the working gas. Simulations demonstrated the strip ionization chamber exhibits excellent energy response, achieving beam loss ≤0.0258% and an average energy loss of 1.08 MeV. This provides a reliable design basis for subsequent hardware fabrication and beam diagnostics algorithms.

Speaker: zhengcan zhang (China Institute of Atomic Energy)

18:10 Research and Development of a Control System for a Domestically Produced 14MeV Medical Cyclotron

Medical cyclotrons are widely used in cancer treatment,nuclear medicine imaging,biophysical research,and other fields,all of which require stable and safe operation.To meet the long-term stable operational requirements of a 14MeV medical cyclotron,a control system for the cyclotron was designed and implemented.This paper first introduces the overall architecture of the control system,followed by detailed descriptions of the hardware structure and software development of each subsystem.Industrially programmable logic controllers were employed for the hardware,while TIA Portal automation software was used for programming.The system has been deployed at Peking University for the production of medical isotopes such as ¹⁸F and ⁶⁴Cu.Validation has shown that the system achieves millisecond-level response times,enables rapid equipment monitoring,exhibits strong anti-interference capabilities, and demonstrates excellent stability and safety,meeting the requirements for the long-term stable operation of medical cyclotrons.

Speaker: 源昊 刘 (China Institute of Atomic Energy)

18:10 Research on Electric Focusing in Central Region of Ultra Compact Cyclotron

Ultra-compact SC cyclotrons for high-intensity medical isotope production pose unprecedented central region design challenges. Strong magnetic fields, compact geometry, and intense space charge effects generate complex focusing conditions where conventional design approaches prove inadequate. In the central region, magnetic focusing is negligible due to minimal azimuthal field variation, while low-energy ions are dominated by electric forces from RF acceleration gaps. High current beam requirements impose stringent electrode design constraints, as poor vertical acceptance directly compromises beam quality. This study investigates electric focusing mechanisms in the central region of an ultra-compact SC cyclotron under development at CIAE for  and H_2^+ dual-beam acceleration. Through mathematical modeling and Hilbert transform-based numerical fitting of simulation data, we quantitatively determine the vertical betatron tune νz and systematically compare electric and magnetic focusing contributions. The methodology combines analytical derivations with numerical techniques to determine focusing parameters from particle tracking simulations. Results reveal the relative importance of electric versus magnetic focusing under intense space charge and strong magnetic field conditions. The findings provide critical insights for optimizing electrode geometry and maximizing vertical acceptance, offering design guidance for improved extracted beam quality in medical isotope production.

Speaker: Yunlong Chai (China Institute of Atomic Energy, Chengdu Cyclotron Science and Technology Co., LTD)

18:10 Simulation Study of an Inductively Heated Ion Source for Electromagnetic Separators​​

High-abundance stable isotopes of nickel possess broad applications and significant demand, which can be prepared using the electromagnetic separation method. The core equipment of an electromagnetic separator for isotope separation is the ion source. To improve the heating efficiency of the traditional Calutron ion source, an electromagnetically induced heating-type ion source is designed. The heating performance of the crucible depends on the configuration of the induction heating power supply and the process design of the inductor. Based on theoretical empirical formulas and electromagnetic field theory, a finite element simulation software, COMSOL Multiphysics, is used to establish a Calutron ion source model. By studying factors affecting heating efficiency.such as the current magnitude, number of turns, spacing of the energized coil, distance between the coil and the crucible, and frequency of the alternating current—electromagnetic-thermal multiphysics coupling simulations are conducted. This helps determine the parameter configuration of the induction heating system power supply. Finally, the inductor design is optimized through orthogonal experiments. The research results can provide practical engineering guidance for the design of electromagnetic induction heating systems in Calutron ion sources.

Speaker: 秀艳 任 (China Institute of Atomic Energy)

18:10 Structural Design and Machining Process Research on RF Cavity for Ultra-compact Multi-particle SC Cyclotron

Ultra-compact multi-particle SC cyclotron being developed by CIAE is intended to be a high intensity cyclotron, especially for H2+ particle and  particle acceleration. Two half-wavelength RF cavities are installed in the valleys of the main magnet independently. The high dynamic beam loading requires high reliability and robust for RF cavity. The structural design and machining process for the two RF Cavities are dedicated investigated. Four kinds of electrical contact technologies such as welding, crimping, spring finger contact and metal wire mesh contact are applied in the structural design of RF cavity to provide flexible and efficient contact, ensure the continuity of surface current path, and then improve the quality factor, Q-value. Based on the analysis of structural deformation and tolerance control, support structure with adjustment function for stems is designed to enhance cavity structure stability under operational conditions as well as the positioning fixtures developed to eliminate the possible errors in the cavity assemble process. The machining process related with water-cooling channel machining, surface treatment, quality verification is also presented in this paper. The RF cavity mechanical design and research show that it provides fundamental basis for the realization of high-performance RF cavities in this ultra-compact multi-particle SC cyclotron.

Speaker: zhan liu (China Institute of Atomic Energy, Chengdu Cyclotron Science and Technology Co., LTD)

18:10 Structural Design and Magnetic Field Optimization of a Combined-Function Quadrupole-Sextupole Magnet

Achieving the design goal of a collision luminosity of 10³⁵ cm^-2s^-1 for the Super Tau-Charm Facility (STCF) poses a critical challenge in optimizing the performance of the injected positron damping ring. This damping ring must damp a 1 GeV positron beam with a large injected transverse emittance (>1400 nm·rad) to an extracted transverse emittance below 11 nm·rad within the 166.7 ms storage time. This imposes stringent requirements on the magnetic field distribution accuracy, damping efficiency, and dynamic aperture of the magnet system. This paper proposes a damping ring design based on combined-function quadrupole-sextupole(QS) magnets. This design achieves an effective balance among key parameters such as emittance control, damping time, and dynamic aperture. Based on this concept, two types of QS magnets with adjustable sextupole to quadrupole field ratios are designed. The paper elaborates on their design and multi-objective optimization methods, with a particular focus on the application of the pole shaping method and asymmetric excitation method. By optimizing the pole face, the impact of higher-order harmonic fields is effectively suppressed. Multiple iterations demonstrate that the major higher-order harmonics in QS magnets are suppressed to the order of 2×10^-4, meeting the damping ring's tolerance for magnetic field errors. This provides a reliable technical foundation for high-luminosity positron beam injection.

Speaker: Jialian Zhang (Huazhong University of Science and Technology)

18:10 The design of the irradiation terminal for the CYCIAE-230 cyclotron beamline

The study of radiation effects and radiation-hardening technology has become increasingly demanding for modern proton cyclotrons in the middle energy range. To meet this requirement, the China Institute of Atomic Energy (CIAE) has designed and constructed a dedicated irradiation terminal downstream of the beamline, following the telescope section, for the CYCIAE-230 superconducting cyclotron complex. The irradiation station uses the double scattering technique to generate a uniformly distributed dose field. The setup incorporates a primary scattering target made of Lexan material and a secondary scattering target composed of lead/Lexan material, functioning as a double scattering beam expansion and uniformization device to form a 3cm × 3cm irradiation field. The Siebers profile is adopted for the secondary scatter. Energy calibration has been studied, yielding a beam energy of 223 MeV at the terminal position when the first scatter is set to a minimal length. The proton particle distribution reveals a dose distribution uniformity of better than 85%. The fluence of the desired field with a measured fluence in the range of 1 × 108 P × sec-1 × cm-2 to 5 × 1011 P × sec-1 × cm-2. The typical irradiation period is adjusted to be in the range of 10 to 1000 seconds, accordingly to facilitate beam gating. The design, geometry, and test results of the beamline and irradiation terminal will be reported in this paper, along with the calibration and online beam diagnostics results.

Speaker: Qiqi Song (China Institute of Atomic Energy)

18:10 The Feature of Magnetic Field Formation of Multipurpose U400R Cyclotron

At the present time, the activities on reconstruction of U400 to U400R cyclotron are carried out at the FLNR, JINR. The new multipurpose U400R cyclotron is intended for production of high intensity, up to 2.5 pmkA, beams of heavy ions from Helium to Uranium with mass to charge ratio A/Z= 4 - 12. The magnetic structure of the new cyclotron will provide a wide range of the magnetic field level from 0.82T till 1.82T what gives the smooth variation of accelerated beams energy 0.8 – 27 MeV/nucleon. For operational optimization of the magnetic field, the 11 radial and 2 pairs of harmonic correcting coils are used. The numerical formation of the magnetic field is carried out. The problems and solutions of U400R magnetic field design are described.

Speaker: Ivan Ivanenko (Joint Institute for Nuclear Research)

18:10 The Impact of Beam Alignment on Extraction Beam

An 18MeV/1mA high-current cyclotron has been designed and constructed at the China Institute of Atomic Energy (CIAE). In this cyclotron, H⁻ ions are accelerated and extracted via carbon stripping foils. To analyze beam loss in this high-current machine, beam dynamics simulations were performed based on measured magnetic field data. The simulations account for beam oscillations, phase slippage, and axial motion of non-ideal beams to determine beam alignment conditions and the influence of Walkinshaw resonance. We computed beam behavior during acceleration and extraction under various alignment conditions, with particular attention to the beam’s particle-optical properties after stripping extraction—including energy spread, envelope variations, and beam loss. The results demonstrate that well-aligned beams exhibit significantly reduced beam loss compared to misaligned beams.

Speaker: ruijin liu (China Institute of Atomic Energy)

18:10 Thermal Deformation Simulation for Ironless High-temperature Superconducting Magnet of CYCIAE-100B Cyclotron

Ironless superconducting cyclotrons, with their advantages of strong magnetic field, compact size, ultralight weight and less sensitive to ambient temperature, show broad application prospects in many areas, such as isotope production, proton irradiation, etc. However, compared to conventional room temperature cyclotron with iron yokes, using superconducting coils as magnet poles and operating at low temperatures to maintain superconductivity necessitates considering thermal deformation of the cold mass during the design of the ironless superconducting magnet. An ironless superconducting cyclotron with 100MeV final energy is under development at China Institute of Atomic Energy. The cooling process within the cryogenic environment induces non-uniform thermal contraction deformation in multi-material components. To avoid concentrated residual stresses, geometric distortion, magnetic field distortion, and the possible quench risk, a three-dimensional finite element model has been established to simulate the thermal structural deformation behavior of the ironless superconducting magnet under several working conditions during the cooling process from room temperature to the operating temperature. The displacement and stress distributions of key components, and their impact on magnetic field homogeneity have been evaluated and an optimized ironless superconducting magnet design has been obtained for the 100 MeV ironless high-temperature superconducting cyclotron.

Speaker: Mr lingyun xia (China Institute of Atomic Energy, Chengdu Cyclotron Science and Technology Co., LTD)

18:10 Thermal Simulation of a High-Power Metallic Beryllium Target for a High-Current Cyclotron Neutron Source

To enhance the reliability and service life of a metallic beryllium (Be) target used in a cyclotron-based neutron source under high-beam-power conditions, this study presents the design and numerical simulation of a solid Be target with a back-cooling structure. Computational Fluid Dynamics (CFD) simulations were performed to analyze the thermal effects induced by a proton beam with an energy of 30 MeV and a current of 1 mA. The results provide critical technical support for the design and longevity improvement of the target system.The simulations demonstrate that heat exchange through the water-cooling channels in the copper backplate significantly reduces the maximum temperature on the target. Furthermore, the insertion of a vanadium interlayer between the Be target and the copper substrate effectively mitigates the risk of hydrogen embrittlement in beryllium. Under specified cooling conditions with typical water chiller parameters, the maximum temperature of the Be target remains well below its melting point (1287°C), thus ensuring safe operation under high-power proton irradiation.

Speaker: JiangLong Xiang (China Institute of Atomic Energy)

18:10 Vacuum Design of the RFQ Injector for a Small-Scale High-Intensity Cyclotron

Using a split coaxial radio frequency quadrupole accelerator (RFQ) as the injector for a small-scale high-intensity cyclotron and adopting a bottom-to-top injection method, the aim is to fundamentally break through the flow intensity limit of the small-scale high-intensity cyclotron. Improving the vacuum level of the RFQ injector can effectively reduce the risk of micro-spark discharge, ensuring stable operation of the accelerator and thereby enhancing overall performance. To ensure stable operation, the vacuum level is set to 10^-6 Pa.Due to the large size of the RFQ electrode head and the relatively small flow conductance between each quadrant, achieving high vacuum and uniformity presents significant challenges. The lateral mechanical dimensions of the RFQ injector have a diameter of 271 mm, and the longitudinal mechanical dimensions are 1616.6 mm. To address these challenges, a molecular pump with a pumping speed of 1200 L/s is selected, and a symmetric double vacuum exhaust window layout is adopted. By positioning the exhaust windows in symmetric locations, each exhaust port can simultaneously act on two adjacent quadrants, establishing a full-space synchronous exhaust mechanism to effectively maintain the high vacuum environment of the RFQ injector, ensuring its stable operation, and thereby enhancing the overall performance and reliability of the entire small-scale high-intensity cyclotron.

Speaker: cong wu (China Institute of Atomic Energy)

20:00 → 21:30 IOC Meeting

Wednesday 29 October

08:30 → 10:10 Cyclotron Applications (4): Session WEA

Convener: Yves Jongen (Ion Beam Applications (Belgium))

08:30 Installation of C70 Cyclotron and the Commissioning of the Sweeper Magnets for SAIF at NRF-iThemba LABS

iThemba LABS is an accelerator based science research facility administered by National Research Foundation (NRF) and has been in operation since 1986. iThemba operates a K200 separated sector cyclotron for research in nuclear physics, radiation biophysics and the production of medical radioisotopes. iThemba LABS has installed an IBA C70 cyclotron, which is phase one of the South African Isotopes Facility (SAIF). The facility includes a 70 MeV H-minus cyclotron and four beamlines for the production of radioisotopes. Decommissioned proton and neutron therapy vaults have been retrofitted to accommodate the cyclotron and bombardment target stations.

Two high-power bombardment target stations have been installed and commissioned in two opposite vaults for the production of radioisotopes. Due to power dissipation in the vacuum windows and the target, heat spots can form during irradiation, which might cause the window and the target to break. In order to reduce the heat spots, two H-type dipole magnets have been designed, installed and commissioned on the two target stations. The magnets are each powered by 1.6 kHz AC power sources with a 90° phase difference between the vertical and horizontal magnets. These magnets sweep the beam in a circular pattern with a radius of 20 mm on the target surface. The presentation will showcase the installation of the C70 cyclotron, design off sweeper magnets coils, electronic setup and magnets commissioning.

Speaker: Dr Joele Mira (iThemba LABS)

09:00 FLNR JINR Accelerator Complex for multipurpose applied research

The Flerov Laboratory of Nuclear Reactions (FLNR) conducts fundamental scientific research alongside extensive applied science activities on its accelerator complex. Key applied research areas include the production of heterogeneous micro- and nano-structured materials; radiation hardness testing of electronic components (avionics and space electronics); ion-implantation nanotechnology and radiation materials science; as well as the production of high-purity radioisotopes and radio-analytical researches. The talk will provide an overview of the current state of the FLNR accelerator complex, the ongoing life science research activities based there and outline the Laboratory's evolution trajectory (include both accelarator instrumentation and applied physics) over the next seven years.

Speaker: Semen Mitrofanov (Joint Institute for Nuclear Research)

09:30 Development and Application of the Cyclotrons for the mA level beam current at CIAE

A great progress on the cyclotron technologies has been achieved and a series of high-intensity cyclotron devices have been developed at China Institute of Atomic Energy (CIAE). The first 14 MeV high- intensity proton cyclotron with an extraction current exceeding 1 mA was independently developed by the department of nuclear technology and application of the CIAE in 2021. The completion of the 14 MeV/1 mA high-intensity proton cyclotron laid the foundation for China’s applications of compact high-intensity proton cyclotrons in neutron source technology. CIAE has successively established the China’s first prototype of a boron neutron capture therapy (BNCT) treatment device based on 14 MeV/1 mA high-intensity proton cyclotron. A 18 MeV/1 mA high-current proton cyclotron was developed successfully as the upgraded BNCT cyclotrons in 2024. Many kinds of BNCT medicine experiments with mice and cells for the hospitals and Universities have been finished. A a new high-intensity cyclotron based on with beam current reaching 3-5 mA is being developed at CIAE. CIAE’s high-intensity cyclotrons are playing a crucial role in the development of nuclear science and the nuclear technology applications，as well as in the production of medical radioisotopes in China.

Speaker: Mr Shizhong An (CIAE)

09:50 Development of Series Neutron Sources at FDS

Neutron sources play a key role in advancing nuclear energy systems and expanding nuclear technology applications. The FDS Consortium has developed a series of neutron sources for various uses, such as the Mini Neutron Generator (MINEG), Small Neutron Generator (SNEG), Compact Neutron Source (CONEG), High Intensity Neutron Source (HINEG), and Volumetric Neutron Source (VNEG). MINEG, with a minimum diameter of 26mm, features long service life, heat resistance, and strong anti-vibration performance. Its pulse timing is adjustable and has been widely used in neutron logging, industrial material analysis, and security inspections. SNEG is a DD/DT neutron source featuring high neutron yield, a compact design, and mobility. It is widely used in neutron radiography, elemental analysis, detector calibration, and nuclear physics experiments. CONEG is a cyclotron-based neutron source with an intensity exceeding 1014 n/s. It is primarily designed for neutronics and shielding validation in advanced nuclear energy systems, as well as for neutron therapy and isotope production. HINEG consists of three phases: HINEG-I, HINEG-II, and HINEG-III. HINEG-I is currently operational and serves as a D-T fusion neutron source with a yield of 6.4 × 10¹² n/s. HINEG-II is a D-T neutron source with a yield exceeding 10¹³ n/s and is located in Chongqing, where it is currently available for experiments. FDS provides an open platform for global collaboration in neutron source research and applications.

Speaker: Wen Wang (International Academy of Neutron Science)

10:10 → 10:30 Coffee break

10:30 → 12:00 Cyclotron Applications (4): Session WEB

Convener: Luciano Calabretta (Transmutex SA)

10:30 Status of AGOR accelerator facility at Particle Therapy Research Center in Groningen, Netherlands

PARticle Therapy REsearch Center (PARTREC) operates the AGOR AVF superconducting cyclotron capable of delivering multiple particle types (protons, light and heavy ions) at multiple extraction energies (from 8 to 190 MeV/u, dependent on particle type).

Following decades of routine operation of AGOR’s cryogenic system, the filling of the cryostat and extraction channels with liquid helium became increasingly unstable. This greatly impeded AGOR’s ability to reliably deliver ion beams and eventually resulted in a prolonged technical shutdown of the facility. A comprehensive cryogenic system overhaul has further enhanced operational stability. The many lessons learned during this exercise will be presented.

Recent upgrades have significantly expanded PARTREC’s capabilities. The new EMC1 extraction element has demonstrated reliable operation. High-intensity beam development (>1 μA) now supports both FLASH radiotherapy and the production of theranostic radioisotopes, notably Terbium. Dedicated dosimetry monitors have been developed to ensure precise dose delivery at ultra-high dose rates. Advancements in ion source technology now allow fine control of proton beam intensity and the inclusion of xenon in the heavy ion cocktail, contributing to more efficient radiation hardness testing. These developments position PARTREC as a unique multidisciplinary hub for cutting-edge research in particle therapy, radiobiology, and nuclear science.

Speaker: Herman Kremers (Particle Therapy Research Center)

11:00 Probing Ion Transport across Crystalline–Amorphous Interfaces through Synchrotron Spectroscopy and Machine-Learning-Potential Simulations

Understanding ion transport across crystalline–amorphous interfaces is essential for advancing next-generation solid-state ionic conductors. In this study, we integrate synchrotron-based spectroscopic and diffraction techniques with large-scale machine learning potential (MLP) simulations to elucidate the microscopic ion transport mechanisms in a partially amorphized natural mineral electrolyte, In situ synchrotron X-ray diffraction and X-ray absorption fine structure (XAFS) analyses confirm the structural stability of the amorphous phase and reveal significant local distortions at the crystalline–amorphous interface. Pair distribution function (PDF) analysis and solid-state NMR further indicate a progressive redistribution of Na coordination environments, with the amorphous fraction reaching nearly 65%. Large-scale molecular dynamics simulations (>50,000 atoms) employing MLPs accurately reproduce the experimental PDFs and uncover a flattened ion-hopping energy landscape at the interface. The combination of surface-sensitive TEY-XAFS and atomistic modeling identifies partially amorphized Na–Na bonding networks as the primary channels facilitating rapid ion migration. This integrated experimental–computational framework—coupling synchrotron characterization with data-driven simulations—offers profound insights into interfacial ion transport and establishes a generalizable strategy for the rational design of high-performance solid electrolytes derived from natural minerals.

Speaker: Wenqian Chen (Shanghai Institute of Applied Radiation)

11:20 The experience of using FLNR JINR cyclotrons for Spacecraft Electronics Radiation Testing

During the flight, spacecraft are constantly exposed to cosmic ionizing radiation. This radiation causes various types of radiation effects in on-board electronics. The most dangerous for modern electronics are single event effects from the impact of individual charged particles of galactic and solar cosmic rays. Charged particles accelerators are used to simulate the impact of heavy ions on electronic devices. Based on the requirements for the active lifetime of spacecraft, orbit and the probability of failure-free operation, the requirements for test facilities were determined and the most suitable type of accelerators are cyclotrons.
The Institute of Space Device Engineering (ISDE) and FLNR JINR have been cooperating for over 15 years in the field of creating single event effects test facilities, developing methodology for conducting tests and their dosimetry. Based on the U-400 and U-400M cyclotrons, FLNR JINR has created an infrastructure for irradiating electronic components with a set of heavy ions from C to Bi with energies from 3 to 40 MeV/A, which, together with the equipment available at the ISDE for setting and measuring the parameters of test objects, as well as their preliminary preparation, allows for a full cycle of testing any electronic components for space applications. The report presents a description of the test facilities and the testing process, the methods and devices used to determine the beam characteristics and metrological support for testing.

Speaker: Pavel Chubunov (Institute of Space Device Engineering)

11:40 Research on Pressure Prediction in Vaccum Systems of Particle Accelerators

Particle accelerators, such as cyclotrons, are intricate and extensive installations that demand meticulous maintenance and precise control over their operational conditions. It is inevitable that some minor malfunctions will occur. These malfunctions can lead to an increase in pressure within the vacuum vessel of the facility. Nevertheless, there are situations during the operation of particle accelerators where a gauge malfunctions while the pressure in the vacuum pipeline remains below the pre-estimated critical value. In such instances, it is not necessary to halt the operation, and the faulty gauge can be conveniently replaced during the next scheduled maintenance.
In this Oral Presentation, a novel approach that integrates Monte Carlo pressure simulation with a linear regression model is introduced. This integrated method is designed to forecast the pressure distribution along the axis of the pipeline in particle accelerators similar to cyclotrons. Through this approach, a trained AI model, which is founded on a linear regression algorithm, can accurately predict the maximum pressure within the vacuum pipeline. Moreover, it can determine the pressure value that a malfunctioning gauge would show by referring to the measurements from other gauges. The outcomes of this research offer significant insights that can serve as a valuable reference for the efficient operation of vacuum systems in particle accelerators.

Speaker: Jie Wang (Xi'an Jiaotong University)

12:00 → 13:30 Buffet Lunch

Buffet Lunch

13:30 → 18:30 Excursion

Plan A: Chengdu Research Base of Giant Panda Breeding
Plan B: Wuhou Shrine and Jinli Folk Customs Area

18:30 → 19:30 Chengdu Specialty Cuisine, supported by Conference Sponsors

Chengdu Specialty Cuisine, supported by Conference Sponsors

Thursday 30 October

08:30 → 10:10 Cyclotron for Hadron Therapy and Isotope Production (5): Session THA

Convener: Mario Maggiore (Istituto Nazionale di Fisica Nucleare)

08:30 Proton therapy status and progress

This report will focuse on clinical difficulties, technical transformation paths, and international cooperation possibilities of proton therapy. The construction history, development scale, core technologies, and clinical achievements of China’s proton therapy centers, especially the progress of proton therapy in Shandong Cancer Hospital will be introduced systematically. In addition, this report also introduces the latest research progress in the innovation of proton therapy technology, multidisciplinary diagnosis and treatment, and the development planning in the future in the areas of proton, heavy, BNCT and other technology research, discipline construction, and international cooperation.

Speaker: Mr Jinming Yu (Cancer Hospital of Shandong First Medical University)

09:00 The NHA C400 cyclotron facility for Hadron Therapy becomes a reality

The NHa C400 is an isochronous cyclotron for cancer therapy which can deliver high intensity of alphas to car-bons at 400 MeV/amu and protons at 260 MeV. It is the first cyclotron-based clinical carbon therapy solution worldwide characterized by K=1600, this is the strongest compact cyclotron. Most of the parts of the cyclotron have been constructed and assembled as well as subsystems such: Superconducting Coil (SCC), Yoke Lifting System (YLS), Cryogenic System, External Injection System (EIS), etc. In parallel, Control Unit cabinets are fitted to the power room, cabled and tested to control subsystem here-above. The EIS is under testing at IBA, Louvain-la-Neuve, the functionalities of this system will be validated before its settle back to Cyclhad. Similarly, the mapping wheel dedicated to the magnetic field mapping of C400 is ready to leave IBA / Louvain-la-Neuve for being installed inside the C400 cyclotron and perform last final in-situ tests. Be-sides the construction and installation of subsystems, the electrostatic deflector as well as the beam probe are in the final stage of design before their production. The paper will present the status of all the components of the Systeme de Recherche et Traitement en Hadrontherapy machine with a focus on the actual assembly of C400 subsystems.

Speaker: Gaelle Gerard (Ion Beam Applications (Belgium))

09:30 Status of Heavy ion cancer treatment machine in China and the perspectives

Heavy ion beam therapy has become an important modality in cancer treatment due to its characteristic Bragg peak and high relative biological effectiveness. Currently, there are 18 heavy ion therapy centers in operation worldwide, with 5 located in mainland China. This paper focuses on the current status of heavy ion therapy facilities in China, objectively describes the technical features of domestically developed heavy ion therapy equipment, and provides an perspective on future technological developments.

Speaker: Mr Jian Shi (Institute of Modern Physics)

09:50 A novel 240MeV superconducting cyclotron SC240 development for proton therapy system in China

Five sets of 240 MeV superconducting proton cyclotrons (SC240) have been successfully developed by Hefei CAS Ion Medical and Technical Devices Co., Ltd. (HFCIM) in collaboration with the Institute of Plasma Physics, Chinese Academy of Sciences. Two of these SC240 have been installed and are currently operational at dedicated proton therapy system in Hefei and Wuhan. The SC240 employs superconducting magnet technology capable of generating a maximum coil field of 4.3 T, delivering a 240 MeV proton beam with currents exceeding 500 nA for proton therapy applications. The cyclotron features a yoke with a diameter of 3 meters and a weight of approximately 70 tons. Two dedicated RF cavities, operating at a frequency of 77.8 MHz and providing up to 100 kV of accelerating voltage, are used to accelerate the proton beam. Three magnetic channels guide the beam from the deflector to the external cyclotron. Specific first-harmonic field compensation has been designed for the first and second magnetic channels. Both the deflector and the magnetic channels are equipped with remotely controlled positioning systems. The maximum beam extraction efficiency of the SC240 has been demonstrated to reach 84% in tests. At customer sites, the extracted beam current consistently exceeds 500 nA. This article presents the key design features of the SC240 cyclotron, including its injection and extraction systems, and provides experimental results from the fourth SC240 unit.

Speaker: Kaizhong Ding (Hefei CAS Ion Medical and Technical Devices (China), Institute of Plasma Physics)

10:10 → 10:30 Coffee Break

10:30 → 12:10 Cyclotron for Hadron Therapy and Isotope Production (5): Session THB

Convener: Jacobus Conradie (iThemba LABS)

10:30 The SPES facility at LNL: status and perspectives

The construction and commissioning of the SPES facility is the flagship project of the INFN Legnaro National Laboratories. The goal is to build a state of the art accelerator facility to carry on research in the fields of Fundamental Physics and Interdisciplinary Physics. The core of the project is represented by a high-intensity cyclotron capable of delivering proton beams at 35-70 MeV with a maximum total current of 750 microA on two simultaneously operated exit ports. A wide range of applications is foreseen spanning from the production and re-acceleration of Rare Isotope beams using the ISOL (Isotope Separation On Line) technique to Research and Development of innovative radioisotopes for medical diagnostics and therapies. The production and supply of radioisotopes to industry is also envisaged. In this contribution, the status of the project will be summarized and the recent commissioning achievements will be illustrated.

Speaker: Tommaso Marchi (Istituto Nazionale di Fisica Nucleare, Laboratori Nazionali di Legnaro)

11:00 Molecular Imaging Probe: Universality & Specificity, Expansion & Innovation

Molecular imaging in nuclear medicine, based on radiopharmaceuticals, enables the diagnosis and evaluation of major diseases at the molecular level. The development and translation of radiopharmaceuticals driven by clinical needs represent the essence of nuclear medicine advancement. Existing radiopharmaceuticals, such as 18F-FDG, hailed as the "Molecule of the Century," play a critical role in the precise diagnosis of malignant tumors, cardiovascular, and cerebrovascular diseases. However, there remains a need to develop diverse molecular probes to meet clinical demands and expand the clinical applications of existing probes. Focusing on the development, translation, expansion, and innovation of radiopharmaceuticals is the future path for the advancement of molecular nuclear medicine.

Speaker: Lan Xiaoli (Wuhan Union Hospital)

11:30 Radionuclides production and medical applications thereof at Peking University

Peking University has built a fully integrated ecosystem for radiopharmaceutical research that spans radionuclide production, drug discovery, and clinical translation, catalyzing innovation at the interface of nuclear science and precision medicine. At its core is the Radiopharmaceutical Research Center (Cyclotron Platform), anchored by the CIAE-developed CYCIAE-14 cyclotron (14.6-MeV protons), 68Ge/68Ga generators, and dedicated radiopharmaceutical synthesis laboratories.
These facilities support the production of a broad radionuclide portfolio—routine isotopes such as 18F and 68Ga as well as novel PET emitters including 64Cu, 86Y, and 89Zr. Peking University has also pioneered domestic production of key therapeutic and generator isotopes, notably 225Ac, 212Pb, and 213Bi, substantially reducing long-standing reliance on imports.
This radionuclide capability underpins extensive screening and preclinical evaluation of radiopharmaceuticals and BNCT agents at Peking University, accelerating the translation of candidates such as BF3-BPA and CTR-FAPI. Beyond clinical applications, isotopes—especially 89Zr and 64Cu—also enable a range of fundamental life-science studies across the university.

Speaker: Zhibo Liu (Peking University)

11:50 Alpha Emitter Radioisotope development plan from natural Thorium Target at IRIS

Several alpha-emitting radioisotopes, Ac-225, Ra-223, and Th-227, can be produced from natural thorium targets, primarily through nuclear reactions induced by a high-energy proton irradiation. These isotopes are of interest for targeted alpha therapy, a cancer treatment approach that utilizes the high energy of alpha particles to destroy cancer cells selectively. Ac-225 radioisotope decays into Bi-209 by emitting 4 alpha and 2 beta particles with a half-life of 9.9 days, which is appropriate for medical applications. In this work, we have tried to produce Ac-225, which is an alpha particle emitting radioisotope by irradiation of Th-232 target with protons in the energy range of 50-70 MeV with RAON cyclotron. Investigating a practical method helps us identify production routes with increased yields. Therefore the present study will be helpful in identifying more effective production methods including chemical separation. Additionally, simulations and numerical calculations of the beam conditions to maximize production yield will be presented. Corresponding to the target thickness of 3 mm, the 70 MeV proton energy is degraded to 50 MeV, while maintaining energy above the threshold. Beam currents about 100 uA irradiated for two days is theoretically estimated in typical actinium-225 yields of 100 mCi, which will be applied to preclinical evaluation of radiopharmaceuticals. In this talk, a brief research activity of ISOL system with 70 MeV cyclotron at IRIS will be presented.

Speaker: Dr B.S. Park (Institute for Basic Science)

12:10 → 13:30 Buffet Lunch

Buffet Lunch

13:30 → 14:40 FFAG and New Projects (6): Session THC

13:30 Beam stacking experiments at KURNS, Japan & ISIS, UK

A key challenge in particle accelerators is achieving high peak intensity. Space charge effects are strongest at injection and typically limit the achievable peak intensity in a ring. The beam stacking technique can overcome this limitation by accumulating a beam at high energy, where space charge is weaker. It also allows the user cycle and the acceleration cycle to be decoupled. In beam stacking, a bunch of particles is injected and accelerated to high energy. This bunch continues to circulate while a second, and subsequent, bunches are accelerated and merged into the first. Beam stacking with large momentum acceptance is only possible in fixed magnetic field machines with a variable accelerating frequency, such as Fixed Field Alternating Gradient (FFA) accelerators.
This talk presents an experimental demonstration of beam stacking involving two beams at the KURNS FFA facility at Kyoto University, resulting in only a slight increase in the momentum spread of the combined beams. However, the intensity of the first beam was significantly reduced due to RF knockout. This resonance phenomenon has been experimentally confirmed in the ISIS synchrotron at the Rutherford Appleton Laboratory, and two mitigation methods were investigated and will be described here.

Speaker: Dr Jean-Baptiste Lagrange (Science and Technology Facilities Council)

14:00 The start-to-end beam dynamics simulation study and its application in the High-Intensity Cyclotron of CIAE

The neutron yield of the neutron source based on the 18MeV/1mA high-intensity cyclotron developed by the China Institute of Atomic Energy (CIAE) has reached 7×10^13 n/s and has been successfully applied in high-resolution neutron imaging and Boron Neutron Capture Therapy (BNCT) experiments. Precise and quantitative start-to-end beam dynamics simulations facilitate a better understanding of the complex beam dynamics behavior of high-intensity beams, which is one of the key technologies for high-intensity cyclotrons. The beam dynamics simulation technology for cyclotrons is relatively mature. However, it is typically implemented independently in each subsystem. During the simula-tion process, assumed initial conditions are introduced multiple times, making it difficult to obtain quantitative results and carry out a global optimization design of beam dynamics. Start-to-end beam dynamics simulation is used in the 18MeV/1mA high-intensity cyclotron. It quantitatively simulates the beam dynamics behavior of high-intensity beams in each subsystem, including the injection line, spiral inflector, central region, accelera-tion region, extraction region, and uniform beam transport line.

Speaker: 天剑 边 (China Institute of Atomic Energy)

14:20 A novel cyclotron concept for isotope production and proton therapy

Cyclotrons for isotope production and proton therapy are becoming increasingly compact and widely used. The main trend is reducing size by increasing the magnetic field strength through superconductivity. I propose an alternative approach: instead of increasing the magnetic field, switch to a different scheme—raise the RF system frequency, making the system more compact. Additionally, by radically reducing ampere-turns in the coils, the coils can be made more compact and energy-efficient, without the need for superconductivity. As a result, the cyclotron becomes just as compact as superconducting models, but much cheaper and simpler.

As an example, an 18 MeV cyclotron with 3 sectors and 3 RF resonators at a harmonic number of 6 (145 MHz) is presented, along with a 230 MeV cyclotron with 4 sectors and 4 RF resonators at the same harmonic number and frequency. The weight and power consumption of these concepts are half that of conventional cyclotrons. A range of cyclotrons from 18 to 230 MeV is under development, sharing the same RF frequency and common components across the lineup.

Speaker: Oleg Karamyshev (Joint Institute for Nuclear Research)

14:40 → 18:30 Scientific Visiting of Fusion Test Facility in Southwestern Institute of Physics, Chengdu

18:30 → 19:30 Banquet, supported by Conference Sponsors

Banquet, supported by Conference Sponsors

Friday 31 October

08:30 → 09:40 Session for Young Scientists (7): Session FRA

Convener: Shizhong An (China Institute of Atomic Energy)

08:30 A General Approach to Radioprotection and Activation Studies for Proton Therapy Facilities

Proton beam therapy has demonstrated over the past 50 years clear advantages compared to conventional radiotherapy. However, the use of high energy protons results in the production of complex mixed secondary neutron and photon fields. The shielding calculations and activation studies require the use of complex computation codes such as the MCNP6 and the FISPACT-2 codes. The use of those codes will be illustrated in the case of the ProteusONE system developed by IBA.
Based upon the use of a superconducting synchrocyclotron (S2C2) delivering 230 MeV proton beams, ProteusONE is a compact PT system with a single treatment room equipped with a compact gantry.
ProteusONE shielding design is based on a detailed patient case mix including a limited number of representative clinical indications and realistic QA activities. It is entirely performed with MCNP6 Monte Carlo simulations including detailed modellings of the concrete vault, the S2C2 cyclotron and the compact gantry. The MC calculations have been validated with a radiation survey performed with an extended-range WENDI-2 rem meter.
Detailed activation studies have also been performed for all aspects of the facility like the cyclotron, the beamline and the concrete walls. A low-activation concrete (LAC) has been developed in collaboration with SCK-CEN in Belgium, reducing considerably the amount of activated concrete generated after 20 years of usage. The LAC has been successfully implemented in several ProteusONE Facilities

Speaker: Frédéric Stichelbaut (Ion Beam Applications (Belgium))

09:00 Research and industrialization progress of 2G-HTS based on MOCVD technology

The progress of HTS technology has been particularly impressive in the last decade. The progress of commercialization of high-temperature superconducting tapes will depend on the degree of mass production and the price.. Eastern Superconductor Science& Technology(Suzhou) Co.,Ltd (Eastern Superconductor) has developed a new MOCVD technology to prepare the REBCO film. The stability of the MOCVD equipment has been significantly improved. Based on a new technological roadmap Eastern Superconductor has developed the complete set of production line for the HTS manufacture, and has achieved efficient production of s of the REBCO HTS tapes.
Here, we could achieve of critical current (Ic) above 1000A-4mm in magnetic field 10T (B//c) at 4.2 K, 10T in heavily doped (11mol.% Zr-added) REBa2Cu3O7-δ (REBCO, RE:Gd,Y) superconducting tapes. And the critical current densities (Je) could reach above 2500A/mm2 at 4.2 K, 20T (B//c) which has been used in the superconducting magnets of fusion project. By adjusting the elemental ratios (RE:Ba:Cu) the average value of lift-factor between Ic at 77 K in self-field and Ic at 4.2K, 20 T (B//c), can be 4.84 in mass production which is tested by PPMS, and all values are within the + /− 30% corridor.

Keywords: REBCO, MOCVD, Flux Pinning, Critical Current

Speaker: YULEI CHEN (Eastern Superconductor Science&Technology(Suzhou) Co.,Ltd,)

09:20 PHYSICS DESIGN OF A 30 MeV ALPHA CYCLOTRON

A cyclotron dedicated to the production of the radio-pharmaceutical Astatine-211 (211At) has been designed. This cyclotron employs an external injection system to introduce alpha particles, utilizing a four straight-sector magnet design and a dual radio-frequency (RF) cavity configuration to accelerate the alpha particles to an energy of 30 MeV. The beam is then extracted from the cyclotron via an electrostatic deflector (ESD). This paper presents an overview of its primary parameters. It subsequently provides a detailed description of magnet systems. Furthermore, extensive beam dynamics simulations are performed. The particle trajectory is tracked through the entire acceleration process to the final extraction, with evaluation of the beam transverse profile, confirming the design’s capability to deliver a high-intensity beam suitable for medical isotope production.

Speaker: Shiwen Xu (Hefei CAS Ion Medical and Technical Devices (China))

09:40 → 10:00 Coffee Break

10:00 → 11:10 Session for Young Scientists (7): Session FRB

Convener: Liangting Sun (Institute of Modern Physics, Chinese Academy of Sciences)

10:00 Cyclotron Design in an Industrial Environment - Continued Learning, Experience and Optimization

Over the past decade, IBA has modernized its cyclotron design tools and accelerator portfolio. This presentation shares key lessons learned, illustrated with practical examples.

Controlling gas stripping is essential to minimize beam losses and component activation. Tools like SPICE models and Molflow+ help simulate vacuum behavior.

Beam dynamics in the central region, particularly phase acceptance and vertical focusing, affect performance. Optimizing the placement of accelerating gaps and implementing effective beam cleaning reduces extraction losses.

While the cyclotron magnet defines the machine’s physical footprint, the total system footprint is also influenced by beam line layout and radiation shielding. Using a larger yoke and optimized beam lines can reduce power consumption without increasing system size. High-temperature superconductors may also reshape future magnet design but they must be weighed against cost.

Output beam energy remains a key factor, especially with evolving needs in nuclear medicine. Adapting fixed energy cyclotron installed base to new energies is vital to support new radioisotope adoption.

Accurate magnetic field mapping is critical for nominal operation and isochronism. FEM analysis allows early correction predictions, reducing mapping time and milling steps. Additional shimming during Smith–Garren beam tests may be required, and new tools help anticipate these, accelerating commissioning.

Speaker: Vincent NUTTENS (Ion Beam Applications (Belgium))

10:30 Comparative study of Ion Bernstein and Ion Cyclotron Wave Generation via Parametric Instability of Whistler Waves in Dusty Plasma

In this manuscript, a comparative study is presented on the generation of ion Bernstein waves and ion cyclotron waves through the parametric instability of whistler waves in dusty plasma. The electron density perturbations associated with the ion Bernstein wave couple with the oscillatory velocity of plasma electrons driven by the whistler pump wave, creating a nonlinear current that drives the whistler sideband wave. Both the whistler pump wave and the whistler sideband wave exert a ponderomotive force on the electrons, which in turn drives the ion Bernstein and ion cyclotron waves. The impact of dust charge fluctuations on this process is investigated, and the growth rate expressions for both the ion Bernstein and ion cyclotron waves are derived. It is observed that the growth rate increases with higher pump wave amplitude, wave number, scattering angle, and dust grain density. However, a decrease in growth rate is seen with increasing dust grain size and electron temperature. Additionally, a comparison reveals that the ion Bernstein wave is more unstable than the ion cyclotron wave, resulting in a higher growth rate for the ion Bernstein wave in dusty plasma

Speaker: Twinkle Pahuja (Amity University)

10:50 A Practical Study on Spot and Layer Reduction in Proton Therapy: A Simulation-Based Validation for Liver Cancer Pencil Beam Scanning Proton Therapy

Abstract
Background and Purpose: The lengthy treatment time of pencil beam scanning proton therapy (PBS-PT) limits its application for mobile tumors like liver cancer. This study aims to combine a high-efficiency beam transport system with spot reduction techniques to significantly shorten treatment time, enabling single breath-hold therapy.
Materials and Methods
We simulated three treatment plans for 12 liver cancer patients: conventional (Plan A), spot reduction only (Plan B), and a combined high-efficiency transport and spot reduction plan (Plan C). Our core innovation involved using BDsim to optimize beam transport, which increased the efficiency of low-energy beams (70 MeV) by 100 times, with parameters validated by TOPAS.
Results
Plan C was significantly superior to Plan A, reducing control points by 69.8% and energy layers by 53.5% (P<0.001), shortening the average single-field irradiation time to under 10 seconds. In contrast, Plan B showed no significant improvement. Plan C maintained dosimetric quality and robustness while boosting efficiency.
Conclusion
This study demonstrates that combining a high-efficiency beam transport system with spot reduction effectively addresses the challenge of long treatment times for mobile tumors, providing a crucial solution for the broader clinical adoption of PBS-PT.
Figure 1: Comparison of Single-Field Irradiation Times and Patient Target Volume Sizes

Speaker: 施延 沈 (Sichuan University)

11:10 → 12:00 Closing Ceremony: Conference Summary

Convener: Tianjue Zhang (China Institute of Atomic Energy)

12:00 → 13:40 Buffet Lunch

Buffet Lunch