ECRIS'26 - the 27th International Workshop on ECR Ion Sources

27 Sept 2026, 16:00 → 1 Oct 2026, 19:00 America/Los_Angeles

Hilton San Francisco - Financial District

Janilee Benitez (Lawrence Berkeley National Laboratory)

This webpage manages the scientific program as well as the submission and editing of abstracts and papers for all attendees of ECRIS'26.

The official website for ECRIS'26 contains information about attending the workshop.

Sunday 27 September

Registration and Happy hour

Monday 28 September

00 Welcome: Welcome session

MOA: Oral session

1 The Development and Routine Operation of FECR Ion Sources

As the first demonstration ion source of the fourth generation, the FECR (First Fourth-Generation ECR Ion Source) has been developed and utilized for the production of highly charged ion beams since July 2024. It now serves as the primary injector ion source for the Low‑Energy intense‑highly‑charged ion Accelerator Facility (LEAF), which entered routine operation in 2025. To date, FECR has accumulated over 5,000 beam hours, delivering ion beams ranging from oxygen to uranium. Given that FECR still employs a hybrid magnet structure, a higher‑field variant—the HFECR (High‑Field ECR) ion source—is under development at the Institute of Modern Physics (IMP) to fully demonstrate the feasibility of Nb₃Sn technology for ECR ion sources. The Nb₃Sn cold mass for HFECR was recently successfully tested up to its design currents in a test dewar. Its final assembly into the operational cryogenic system is scheduled for completion by the end of 2026. This paper presents the operational status of the FECR ion source and discusses the progress in developing the HFECR cold mass.

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

2 TELAMONES & PANDORA: New Perspectives of R&D on ECR Ion Sources at INFN-LNS

The evolution of ECR ion sources is driven by the demand for higher charge states, beam intensities and reliability, requiring advances in plasma physics, microwave engineering and superconducting technologies. To support these developments, INFN-LNS is building two research infrastructures: TELAMONES and PANDORA. TELAMONES will host an AISHA source operating at 18 and 21 GHz for beam development, plasma studies and RF/microwave propagation investigations, together with a second setup dedicated to high-intensity beams. PANDORA extends the role of ECR plasmas from ion-beam production to a subject of research itself, aiming at the first measurement of radionuclide β-decay rates in plasma conditions relevant to nuclear astrophysics through a comprehensive online diagnostic system.
During the upgrade of the LNS accelerator complex, the installation of a second AISHa source at CNAO provided a valuable test bench for improving beam availability, reproducibility and maintenance procedures. The experience demonstrated the feasibility of adapting advanced superconducting ECR technology to hospital environments, where reliability and operational continuity are mandatory.
Building on these results, the development of SC-AISHa, a new ECRIS designed for operation up to 28 GHz in High-B mode with enhanced magnetic confinement, is ongoing. This paper presents the current status of TELAMONES and PANDORA and outlines the main research and development activities.

Speaker: Luigi Celona (Istituto Nazionale di Fisica Nucleare)

3 Upgraded Injector Design Based on ECR Ion Sources for High Charge-State Ion Beam Production at GSI

To address the increasing demand from the facility and its user community for high-duty-cycle ion beams, the development of a continuous-wave (CW) linear accelerator (LINAC) is foreseen in the coming years. The corresponding injector is designed to deliver ion beams with mass to charge ratios up to 6 in CW operation and up to 8.5 in pulsed mode, with beam intensities exceeding those currently achievable with the existing CAPRICE source. In order to meet these specifications, systematic studies have been performed to enhance the source performance. An optimized configuration of the plasma chamber and injection plug is currently under development, aiming at improving plasma heating and confinement, extraction efficiency, and overall beam stability. In parallel, the implementation of an 18 GHz electron cyclotron resonance ion source is being pursued to extend the accessible charge-state distribution towards higher charge states for heavier elements.
This contribution reports on the ongoing developments, the optimization strategy, and the expected beam performance of the upgraded injector systems.

Speaker: Fabio Maimone (GSI Helmholtz Centre for Heavy Ion Research)

10:30 Break

MOB: Oral session

4 Critical Progresses on Low-cost Compact Carbon Positive Ion Mass Spectrometry (C-PIMS) at Peking University

Positive Ion Mass Spectrometry (PIMS) represents an advanced methodology for radiocarbon dating, operating on principles distinct from those of Accelerator Mass Spectrometry (AMS). Current research mainly focuses on the miniaturization carbon ion source and high charge exchanging cell for a prototype PIMS system. At Peking University (PKU), several PIMS-related experiments have recently yielded promising results. First, a compact gas-fed 2.45 GHz Microwave Driven Ion Sources (MDISs) with an all-permanent-magnet design was developed and it already consistently generates more than 686 emA of C2+ in DC mode, demonstrating the robust high-charge carbon ion production required for PIMS. Second, a non-metallic gas charge exchange target was manufactured and its charge exchange efficiency reaches up to 6.1% for C2+ to C-, and a C- beam current of 19 μA was obtained. In addition, a 260 eμA C- beam at 45 kV is also obtained from C+ ions with a charge exchange efficiency of 7%. A novel analytical approach utilizing C+ ions for 14C measurement in PIMS was proposed and a patent based on C+ to C- has been authorized. A beam dynamics design for a future C-PIMS beamline was conducted to optimize its 14C transmission efficiency. The PIMS system occupies only an area of approximately 4.1 m×2.2 m, while substantially reducing operational costs.

Speaker: ShiXiang Peng (Peking University)

5 Progress on the Magnetic-Field Profile Upgrade of the Texas A&M 14.5 GHz ECR Ion Source

An upgrade of the magnetic field profile of the Texas A&M 14.5 GHz electron cyclotron resonance ion source, ECR2, is underway, guided by well-established magnetic-field scaling rules. The axial magnetic field at the injection end has been increased by installation of a modified lower-carbon steel plug and replacement of the aluminum biased disk with a steel one. The radial field is being enhanced at the poles through replacement of the existing hexapole assembly with new NdFeB permanent-magnet bars, with the field direction rotated relative to the original design. These bars will be installed in a new, better-cooled aluminum plasma chamber, whose construction was prompted by a recent vacuum break in the inner wall of the existing chamber, which was subsequently repaired. Central to these coupled efforts, optimization studies of the radial magnetic field profile through detailed modeling of the magnet assembly are being performed in COMSOL Multiphysics, with results to be benchmarked against PANDIRA calculations from the original ECR2 design. Once validated, the COMSOL framework will be further used to conduct thermal and demagnetization analyses to guide the cooling-system design of the new chamber and assess long-term magnet integrity. Collectively, these modifications are expected to significantly improve plasma confinement and stability, leading to an increase in high-charge-state ion production.

Speaker: H.I. Park (Texas A&M University)

6 Recent Beam Production Improvements and Upgrades of the ATLAS ECR Ion Sources

The Argonne Tandem Linac Accelerator System (ATLAS) continues to receive requests for increasing beam intensities, energies, species, and time on target. Over the past few years, most of the ion beams delivered to experiments have been produced by the two ATLAS Electron Cyclotron Resonance Ion Sources (ECRIS), ECR2 and ECR3. While demands increase, the ATLAS team continues to make improvements and upgrade subsystems to expand beam capabilities. An infrastructure upgrade for cooling water has increased the operating range of the ECR2 solenoids, leading to an improved 136Xe28+ intensity of 24 euA as compared to the previous best of 15 euA. The ATLAS Multi-User Upgrade (AMUU) project will allow simultaneous delivery of beams from the ECR2 and the Electron Beam Ion Source (EBIS) to separate experiments. The front-end feasibility has been demonstrated with the interleaving of a 10 enA 84Kr17+ beam from the ECR2 and a 100 epA 133Cs27+ beam from the EBIS with subsequent acceleration through the PII and Booster linacs. Lastly, ECR3 now has the capability of producing tritium (3H) ion beams and has successfully delivered its first tritium beam to an experiment. Details of these improvements are presented.

Speaker: Jake McLain (Argonne National Laboratory)

12:30 Lunch

MOC: Oral session

7 Towards a >40 GHz ECR Ion Source with Nb3Sn Magnets: Fabrication and Performance of a Mirror Magnet with a Prototype Nb3Sn Sextupole Coil

Superconducting electron cyclotron resonance (ECR) ion sources are in operation around the world for heavy ion accelerators. These sources rely on magnets wound using Nb-Ti conductors. Due to its higher magnetic field limits, Nb3Sn conductors can result in a magnet providing stronger magnetic fields to enable higher intensity high charge beams. In this context, LBNL is collaborating with the FRIB to build a sextupole-in-solenoid magnet for a >28 GHz superconducting ECR ion source. A prototype Nb3Sn sextupole coil has been fabricated. It is tested using a mirror magnet structure. Earlier on we reported the tooling and process for the prototype coil fabrication. Here we report on the magnetic design and mechanical analysis of the mirror magnet assembly for prototype coil testing, and magnet assembly using a bladder and key
method assisted with strain gauges and fiber optics measurements. Additionally, we report the test results in liquid Helium. The magnet reached a conductor peak field of 9.7 T with 1640 A, achieving 75% of its short sample limit, after three spontaneous quenches. It also carried 1200 A for 10 minutes without quenching. The results qualifies the sextupole coil built for use to build a >40 GHz ECR Ion Source. We report on characteristics of the mirror magnet relevant for the ECR Ion Source, including flux jump induced voltages and quench protection. We also provide
a prospect of designing and fabricating a >40 GHz ion source magnet .

Speaker: Tengming Shen (Lawrence Berkeley National Laboratory)

8 Design and Modeling of the Superconducting Magnet System of an ECRIS for Applications in Graphene Doping

Electron Cyclotron Resonance Ion Sources (ECRIS) are devices capable to provide a constant flow of ions at high currents. The ions extracted from the ECRIS can be used in material doping applications. In this paper, we present the design of an ECRIS magnetic system for graphene doping. The design is based in the use of Cable-In-Conduit superconducting cable and a superferric sextupole. This magnetic system allows a simpler design, the use of less amount of superconducting cable, and the ability to variate the magnetic field strength to tune it according to the specific doping application or to the microwave frequency employed for electron heating. The results of numerical simulations show that this system generates a magnetic field in the B-minimum configuration with a maximum strength of 1.0 T near the gas injection side and a sextupolar field in the middle of the plasma chamber with a maximum of 0.8 T in the wall. The system can be adjusted to be used with microwaves in the frequency range 1–10 GHz. Simulations of nitrogen plasma generation and confinement show that an ECRIS with this magnetic system allows electron and N^+ ion densities of at least 9.6E18 m^−3 in the center of the plasma chamber for 10 GHz microwaves at 1 KW and a nitrogen gas at a pressure of 1 Pa.

Speaker: Marco Antonio Ortiz Villicaña (Universidad Autónoma de Zacatecas "Francisco García Salinas")

9 Ultracompact Low-Power ECR Sources: Bridging Micro-Scale Plasma and Industrial Beam Applications

Recent developments at CAMECA build on the pioneering work of P. Sortais on ultracompact Electron Cyclotron Resonance (ECR) micro-sources, extended into the TES (Tubular ECR Sources) family. These devices rely on microwave-driven micro-cavity discharges operating at very low power (~1 W), defining a regime that departs from conventional ECR sources requiring tens to hundreds of watts.
Stable ECR plasmas are sustained in sub-centimeter cavities combining strong magnetic field gradients and efficient microwave coupling. The resulting sources, integrated in compact CF-standard footprints (from CF40 to CF100 depending on beam energy desired), require no active cooling and enable straightforward integration into UHV instrumentation while offering high reliability and long lifetime due to their filament-free design.
Despite their compactness, these sources generate high-brightness ion and electron beams, with intrinsic performance exceeding conventional RF plasma sources used in SIMS, confirming efficient ECR operation at the micro-scale. Their unique versatility allows operation as ion, electron, or negative ion sources by solely adjusting operating conditions.
These performances open perspectives for next-generation SIMS instrumentation, improving beam stability, brightness, and flexibility in industrial environments. In parallel, new developments include high-temperature ECR configurations enabling metallic ion production, extending the capabilities of these compact sources.

Speaker: Jerome Vernieres (Cameca (France))

10 CUBE-ECRIS - lessons learned

CUBE-ECRIS is a permanent magnet prototype ion source operating at 11 GHz frequency. It was constructed to (1) study the electron heating and the stability of the plasma in a minimum-B quadrupole magnetic field topology, (2) demonstrate high-charge state ion production and beam transport from the quadrupole field through an extraction slit, and (3) support the development of a net-zero front-end for Time-of-Flight Elastic Recoil Detection Analysis (ToF-ERDA) facility. We summarise experimental results, e.g. ion beam currents, bremsstrahlung spectra, afterglow transient peaks and instability-induced electron and ion bursts, and discuss the main limitations i.e. available microwave power and beam losses in the extraction and low energy beam transport of the CUBE-ECRIS. We describe possible upgrades to the permanent magnet configuration and the extraction system that would alleviate some of the limitations observed in the experiments. Finally, we discuss the results of a recent experimental campaign where the CUBE-ECRIS was coupled with an adjustable permanent magnet dipole to demonstrate the production, separation and transport of high charge state argon beams meeting the requirements of the ToF-ERDA application.

Speaker: Olli Tarvainen (Science and Technology Facilities Council)

Tuesday 29 September

TUA: Oral session

11 ECR Ion Source for molecular hydrogen ions for NASA Space Radiation Laboratory at Brookhaven National Laboratory

A hydrogen molecular ion ECR ion source is being developed to provide proton beams to the NASA Space Radiation Laboratory (NSRL) at Brookhaven National Laboratory. In the past, proton beams at NSRL were supplied by the 200 MeV LINAC or the Tandem accelerator. However, NSRL has requested the capability to deliver protons from the EBIS beam line as well, in order to achieve simpler and more cost-effective operation. Recently, the upgraded EBIS successfully provided hydrogen molecular ion beams, which were accelerated and converted into protons at NSRL through foil stripping. Although this approach provides a sufficient number of protons for many users, there remains a demand for higher beam intensity. To meet this demand, the development of a hydrogen molecular ion source optimized for high-intensity operation has been proposed. The ECR ion source can be installed on the EBIS heavy-ion beam line. To satisfy operational requirements such as short beam pulses, low gas load to downstream components, and a compact system layout, a pulsed ECR ion source is being developed. In this presentation, the concept of the hydrogen molecular ion ECR ion source and the current status and progress of its development will be presented.

Speaker: Shunsuke Ikeda (Brookhaven National Laboratory)

12 High Current DC H2+ / H3+ Beams Generation with PKU Type Miniaturized 2.45 GHz Microwave Driven Ion Source

Recently attention was paid to produce high current high fraction DC H2+, H3+ generation with PKU (Peking University) Type Miniaturized 2.45 GHz Microwave Driven Ion Source (MMDIS) atour ion source group. A 22 mA DC H2+ ion beam with its fraction of 70% was obtained last year [1]. This data was updated to 24 mA newly. To overcome space charge effect, activation and Lorentz stripping limits within the Superconducting Ring Cyclotron and other accelerators like TRIUMF 520 MeV cyclotron, SCENT project, IsoDAR etc., H3+ becomes the key support for those high intensity proton facilities. At PKU, with the same MMDIS a 7.6 mA DC H3+ ion beam was generated later this year. Its H3+ fraction can reach up to 68.5%. This will offer practical benefits, particularly in cancer treatment and astronomy.

[1] Cui B, Peng S, Zhu J, Dong Y, Guo Z, Chen, New progress on DC H2+ beam generation: Tens of mA output and 70% fraction from a 2.45 GHz microwave driven ion source. Letter, Chin. Phys. B 34, 085203 (2025)

Speaker: ShiXiang Peng (Peking University)

13 D-D Fusion with Low Energy Deuteron Beam at Nusano Ion Source

The deuterium-deuterium (D-D) fusion reaction has long been of interest to the field of nuclear physics. Existing research involving bombarding a deuterium-loaded target with incident deuteron beam has characterized how the D-D reaction cross section depends on incident beam energy, but the tens-of-keV range remains comparatively unexplored. Using the Nusano ion source, the D-D reaction over the 30-60 keV energy range has been studied using copper, stainless steel, and graphite targets, loaded with deuterium by the incident beam, at various beam currents. The reaction has been evaluated via the neutron dose rate measured during bombardment, allowing the neutron yield to be correlated with beam energy, current, and material. The resulting data helps characterize D-D neutron production in this sparsely studied energy range and provides insight into the underlying cross section behavior.

Speaker: Liangyi Chen (Nusano)

10:30 Break

TUB: Oral session

14 Solid Beams Operations with the 28 GHz Electron Cyclotron Resonance (ECR) ion source at the Facility for Rare Isotope Beams (FRIB)

This paper review solid beam operations from the Superconducting ECR ion source at the Facility for Rare Isotope Beams (FRIB) at Michigan State University. FRIB delivers beams for nuclear physics experiment after acceleration through a superconducting linac. The current beam list is composed of 25 different isotopes out of which two third are solid elements. This list will continue to expand over the next few years to reach over 30 isotopes. Three types of oven are used at FRIB for the production of vapor depending on the temperature needed to reach a vapor pressure typically in the 1-10 mTorr range. A cartridge-based oven is used in the lower temperature range up to 600 ⁰C suitable for element such as Zinc, Selenium or Calcium. A new version is in development to extend operation of this design to approximately 800 ⁰C that we intend to use for the production of Molybdenum from Molybdenum Trioxide. A simple resistive oven is used to cover the range of 800 ⁰C to 1200 ⁰C which works well for Lead, Bismuth, Samarium or Silicon while an inductive oven is used up to 2000 ⁰C primarily used for Uranium production from uranium oxide but also used for Nickel, Germanium and Platinum. This paper review the operations of these oven as well as performances and efficiencies achieved for the solid beams.

Speaker: Guillaume Machicoane (Facility for Rare Isotope Beams)

15 Development of Intense 50Ti, 51V and 54Cr Metallic beams, from MIVOC to HT Ovens

Development of Intense 50Ti, 51V and 54Cr Metallic beams, from MIVOC to HT Ovens

B. Gall, Z Asfari, L Charbonnière, C Charpentier and M Filliger,

Université de Strasbourg, CNRS, IPHC UMR 7178, 67037 Strasbourg, France

The 48Ca beams associated to the heaviest actinide targets available enabled the discovery of the heaviest superheavy elements (SHE) known up to oganesson. Search for new SHE needs now to replace the calcium by 50Ti, 51V and 54Cr. These latter beams are not only more difficult to produce, but they are also needed with significantly higher intensities in order to overcome the drop in SHE production cross sections for new elements.
The present contribution will highlight in a first part the developments made in order to get several particle micro amperes on target using isotopic MIVOC compounds of titanium, vanadium and chromium. The best results obtained will be discussed together with the limitations associated to the vacuum level in the ECR ion source.
In a second part, we will discuss the development of even more intense beams through high temperature inductive micro evens. The oven development will be presented and the first emittance measurements will be discussed. The last section will be devoted to the preparation of highly enriched isotopic metallic pellets of 50Ti and 54Cr.

[1] H. Koivisto et al., NIM B 187 (2002)111,
[2] J. Rubert et al., Nucl. Instr. & Meth. Phys. Res. B 276 (2012) 33–37.

Speaker: Benoît gall (Université de Strasbourg)

16 Pfeiffer Presentation

17 Pantechnik Presenation

12:30 Lunch

TUC: Oral session

18 Three-Dimensional Particle-In-Cell Simulations of the Electron Cyclotron Resonance Ion Plasma Accelerator

This study reports the results of kinetic plasma simulations of the Electron Cyclotron Resonance Ion Plasma Accelerator (ECRIPAC). ECRIPAC* is an original compact plasma accelerator capable of producing high-energy pulsed ion beams by leveraging established and reliable ECR ion source technologies, without the need for axial radiofrequency cavities or high-power laser systems. The concept is based on the gyromagnetic autoresonance of plasma electrons in a time-varying magnetic field, followed by the axial acceleration of ions by the plasma space-charge electric field within a magnetic field gradient, resulting in ion energies approaching 100 MeV per nucleon.
After a brief overview of the ECRIPAC operating principles**, three-dimensional electromagnetic Particle-In-Cell simulations performed with the open-source code WarpX*** are presented for a preliminary He2+ accelerator design****. The simulations provide a detailed characterization of the plasma dynamics throughout the different stages of the ECRIPAC operating cycle, including electron heating, charge separation, plasma compression and ion acceleration. Particular attention is devoted to the evolution of key plasma parameters and to the identification of kinetic instabilities that affect the plasma bunch evolution and limit the accelerator performance. These results provide insight into the underlying acceleration mechanisms and establish a basis for the optimization of future ECRIPAC designs.

Speaker: Andrea Cernuschi (Laboratoire de Physique Subatomique et de Cosmologie, Centre National de la Recherche Scientifique, Université Grenoble Alpes)

19 Methods to reduce the computation time and memory to calculate the plasma potential in electron cyclotron resonance ion source

The Debye length in an ECRIS plasma can be as low as tens of micrometers while the confining plasma chambers are tens of centimeters in extent. Resolving the Debye length when solving the Poisson equation on a mesh inside these chambers requires an extremely fine mesh density, requiring large amounts of computer memory and resulting in long solution times. Methods to reduce the mathematical problem size applicable to ECRIS are presented and discussed for the finite difference method. Specifically, a new method consisting in ordering the mesh in an enantiomorphic way is presented, leading to a matrix solving complexity reduced by a factor of two. Examples of computation gains against classical solving are presented.

Speaker: Thomas Thuillier (Lawrence Berkeley National Laboratory)

20 Optical emission spectroscopy diagnostic for beam monitoring in ion sources

Non-interceptive online diagnostics are essential for monitoring ion sources, particularly during physics experiments. Optical emission spectroscopy, already used in other laboratories, has been deployed at GANIL. The light emitted by the plasma is captured by a CCD camera placed behind a glass window aligned with the ion source and by an optical fiber connected to an optical spectrometer (350-1000 nm).
Initial tests were carried out with Ar + He plasma, with an intensity of 80 μAe of 40Ar⁹⁺ measured after the mass separator [1]. Additional studies were performed online in 2025 and 2026 with several ion beams. Optical measurements made it possible to track changes in the light intensity of the identified wavelengths over time. The use of this technique also provided access to new information (effect of temperature variation, presence of pollution, evaluation of the metal ion population) and helped to better identify the needs for optimizing the source settings.
These various measures demonstrate the value of developing a dedicated diagnostic tool to continuously monitor beam stability and assist operators during experiments. To this end, initial work has been carried out on automating the analysis of measured optical spectra. This represents the first step towards ultimately achieving complete automation of source adjustments.
[1] Dubois M., Lemagnen F., Gouleuf L., Metayer V., Osmond B., GANIL ion sources: optimisation for operation, Proceeding of ECRIS Workshop (2024)

Speaker: Alexis Ribet (Grand Accélérateur National d'Ions Lourds)

21 X-ray Imaging and Spectroscopy Technique via Pin-Hole camera on 3rd generation ECR Ion Source Plasmas

The PANDORA (Plasmas for Astrophysics, Nuclear decay Observation and Radiation for Archaeometry) project features magnetized plasmas in compact ECR traps as experimental environments for fundamental astrophysics and nuclear physics. A new algorithm for X-ray imaging in Single-Photon Counting mode was adopted, enabling space-resolved spectroscopy for magneto plasma properties investigations (e.g. local thermodynamic parameters, confinement dynamics). Both the diagnostics setup and the algorithm were developed over ten years and tested multiple times on ATOMKI Laboratory’s 2nd generation ECRISs. A step forward in the algorithm optimization was recently made via an AI-based MATLAB model to yield faster analysis of plasma spectra enhancing energy and spatial resolutions, maximizing the S/N ratio. While well-established on 2nd generation ECRIS, the technique has never been applied to a 3rd generation one. To address this challenge, we developed a high-fidelity Geant4 simulation of the LBNL’s VENUS ion source. The simulations serve as a critical tool to predict the expected counting rates and quantify the X-ray fluxes, based on volumetric spectra, thus ensuring the CCD safety against saturation or ionizing radiation damage. An experimental X-ray imaging campaign on VENUS is scheduled, and preliminary results will be presented and compared with the simulation aiming to establishing safe operational limits—through RF frequency, power, magnetic field, and pressure parameter scans.

Speaker: Bianca Peri (Istituto Nazionale di Fisica Nucleare, Laboratori Nazionali del Sud)

Poster session

22 Ion Source Test Stand Upgrades and RFQ Integration at HIT

Since the start of clinical operation in 2009, more than 10,000 patients have been treated at HIT with proton, carbon, and helium ion beams. Three Supernanogan ECR ion sources are operated for routine clinical beam delivery.

A fourth Supernanogan ECR ion source is available at the HIT test bench for studies on source optimization and injector development. As part of an ongoing measurement campaign, the influence of dual-frequency microwave heating using 14.5 GHz and 18 GHz on the extracted ion beam is being investigated. Beam characterization is performed by beam current and beam profile measurements.

This contribution presents the experimental setup and first results of the dual-frequency studies. In addition, an outlook on further activities at the HIT test bench is given, including the commissioning of a newly developed 4-rod RFQ for the HIT injector linac, aimed at increasing particle transmission and supporting future high-intensity operation.

Speaker: Tim Winkelmann (Heidelberg Ion Beam Therapy Centre)

23 Current Status of the 28 GHz ECR Ion Source at RAON

RAON is a heavy-ion accelerator facility at the Institute for Basic Science, designed to provide high-intensity ion beams with a maximum beam power of up to 400 kW. Currently, various ion beams, such as Ar and Ne, are delivered using a 14.5 GHz electron cyclotron resonance ion source. To meet future beam requirements, a 28 GHz ECR ion source is being prepared at RAON. The ion source consists of a superconducting magnet system and is designed to operate with both 18 GHz and 28 GHz RF systems. As part of the commissioning process, magnet ramp-up tests have been performed, and the beam extraction and low-energy beam transport systems are being prepared. The extracted beam will be transported using an electrostatic quadrupole system, and the beam current will be measured with a Faraday cup. This poster presents the current preparation and commissioning status of the 28 GHz ECR ion source, including the superconducting magnet, RF system, beam extraction and transport components, diagnostics, control system, and planned commissioning activities.

Speaker: Dr Eunhun Im (Institute for Basic Science)

24 Simulation and Design of an Einzel Lens for Focusing an Ion Beam into an EBIT

The Smithsonian Astrophysical Observatory's (SAO) Electron Beam Ion Trap (EBIT) traps highly charged ions for astrophysical spectroscopy. Elements are injected as neutral gas or singly charged ions via a Metal Vapor Vacuum Arc (MeVVA) source, then successively ionized by a dense, quasi-monoenergetic electron beam. At high beam currents, the beam's space charge draws MeVVA ions into the EBIT's Penning-like trap. As current decreases, this focusing weakens and injection efficiency drops sharply. This work presents a three-electrode Einzel lens designed to address this limitation and increase ion extraction.
The MeVVA ion source produces a divergent, off-axis beam, focused by the downstream Einzel lens into the EBIT trap. Trajectories were simulated in SIMION using trap electrode geometries imported from the CAD model. The EBIT's superconducting magnet, also investigated, induces only slight helical motion with under 1 mm radial excursion and can thus be neglected when optimizing the lens. Two electrodes were split in half, adding steering functionality to focus the off-axis ions onto the optical axis. Assuming uniform launch angles and a monoenergetic beam, the optimized lens yields a roughly five-fold increase in ion intensity at the EBIT center versus the unassisted case. These results motivate fabricating and installing the lens as a practical beamline upgrade.

Speaker: Laurenz Birnbaum (Appalachian State University)

25 Status of the ECR2 Upgrade at Argonne National Laboratory

Preparations are underway for the upgrade of the ECR2 ion source at the Argonne Tandem Linac Accelerator System (ATLAS) to enhance its beam capabilities. The upgrade incorporates a higher wall field hexapole, optimized iron shaping and materials, and higher solenoid operating currents to support 18 GHz RF heating. The components of the permanent magnet hexapole have been received, and fabrication of the plasma chamber is progressing. The presence of Ac-227 contamination within the source, vacuum vessels, and low-energy beamline has expanded the project scope, requiring the replacement of more components than originally planned. Work control documents for the safe handling and disposal of the contaminated components are being drafted and reviewed. Installation of all components is scheduled for January 2027, with commissioning to follow immediately.

Speaker: Richard Vondrasek (Argonne National Laboratory)

26 Electron Temperature Studies of Plasma in the 3rd Generation VENUS ECR Ion Source

Third-generation electron cyclotron resonance (ECR) ion sources utilize superconducting magnets to achieve the enhanced plasma confinement necessary to produce intense, highly-charged ion beams. However, since plasma density increases proportionally with the square of resonance frequency, the higher radiofrequency (RF) and higher power used to heat the plasma produce a greater number of very energetic electrons, which are the source of the bremsstrahlung emission that poses a significant thermal load to the 4 K liquid helium cryostat. Because traditional plasma diagnostics are destructive, we analyze non-invasive axial bremsstrahlung emission from the hot electrons, ascribing a spectral temperature to the measured spectrum under varying magnet, vacuum pressure, and RF parameters. The work presented here confirms previous measurements and investigates effects on charge state distributions, x-ray emission properties, and cryostat heat load. Extrapolating the electron heating this way will also inform the heat shielding design for the fourth-generation MARS-D ECR ion source.

Speaker: Nishi Intwala (Lawrence Berkeley National Laboratory)

27 CHIPS$^{2}$: A 60 GHz ECR Ion Source with Superconducting Coils for High-Intensity Multicharged Ion Beams

High-frequency ECR ion sources are of paramount importance for high-power accelerators, as they provide the high-intensity ion beams required for nuclear physics experiments.

For several years, LPSC has been developing and refining a 60 GHz ECR ion source. Following the decommissioning of the SEISM source (Sixty-gigahertz Ion Source using Megawatt magnets), which relied on resistive copper coils for magnetic confinement, a new 60 GHz ECR source featuring superconducting coils is currently under construction. This new source, named CHIPS² (Cusp High Ion density Plasma Superconducting Source), aims to deliver high-intensity multicharged ion beams close to 100 mA, thanks to a significantly larger plasma volume (21 liters vs. 33 cl for SEISM) and an upgraded 60 GHz gyrotron operating in continuous wave mode.

This paper presents recent results on the progress and construction of the source coils, the advancement in the gyrotron control and automation system, as well as strategic choices and the preliminary design of the extraction system. These developments are crucial steps toward achieving the complex goal of generating a very high-intensity ion beam.

Speaker: Thomas Andre (Laboratoire de Physique Subatomique et de Cosmologie)

28 Conceptual Design and Current Status of an Additional 14.5 GHz ECR Ion Source for RAON

RAON (Rare isotope Accelerator complex for ON-line experiments) is a heavy-ion accelerator facility constructed through the Rare Isotope Science Project (RISP) to support rare-isotope science in Korea. Since 2024, RAON has delivered stable-isotope beams, including Ar, O, and Ne, using a 14.5 GHz Electron Cyclotron Resonance Ion Source (ECRIS) for user experiments. Recently, rare-isotope beam delivery from the Isotope Separation On-Line (ISOL) system has begun, increasing the need for reliable and flexible ion-source operation for various beam species. To improve beam availability and operational flexibility, RAON plans to operate multiple ion sources: the existing 14.5 GHz ECRIS, a 28 GHz ECRIS under development, and an additional 14.5 GHz ECRIS. The new source will be used for preliminary beam tests with stable isotopes, optimization of operating conditions, and backup operation during maintenance of the primary source, thereby supporting more reliable accelerator operation. This paper presents the conceptual design and current development status of the additional 14.5 GHz ECRIS. Based on operational experience with the existing source, the required performance, major components, and planned operation scenarios are described.

Speaker: Jeongil Heo (Institute for Basic Science)

29 Development and Performance Verification of a 4 kW LDMOS-Based Solid-State Power Amplifier for Superconducting QWR and HWR Cavities

A 4 kW continuous-wave (CW) LDMOS-based solid-state power amplifier (SSPA) has been developed for the low-energy superconducting linear accelerator (SCL3) at the IBS heavy-ion accelerator facility. The system provides RF power to 81.25 MHz quarter-wave resonators (QWRs) and 162.5 MHz half-wave resonators (HWRs). The amplifier features a modular parallel architecture comprising six 1000 W PA pallets integrated via a multi-stage RF combining network. To ensure reliability against cavity detuning and impedance mismatches, a dual reflection-protection scheme utilizing both pallet-level and high-power output circulators was implemented. Performance evaluations demonstrated a saturated CW output power above 4 kW, a power gain of 70.4 dB, and an AC-to-RF efficiency of 54%. Harmonic and spurious emissions were suppressed below −34.8 dBc and −75 dBc, respectively. Long-term stability tests over 12 hours with a ±1 °C coolant temperature fluctuation yielded output variations within ±1% and phase deviations within ±5°. Additionally, full-reflection tests under OPEN and SHORT conditions confirmed stable operation at the rated power without protection trips. These results verify that the developed SSPA satisfies the stringent requirements for superconducting cavity operations and is highly suitable for continuous accelerator operations.

Speaker: Sangyoon Bae (Institute for Basic Science)

30 Development Status of the Next-generation 45 GHz ECR Ion Source MARS-D

The 3rd-generation ECR Ion Sources, constructed with Nb-Ti superconducting wires and the conventional racetrack-and-solenoid structure, have been successfully operated for over two decades, achieving operating frequencies up to 28 GHz and utilizing about 90% of the critical current of the Nb-Ti wire. A Mixed Axial and Radial field System (MARS) ECRIS is being developed at LBNL. This system, which consists of an innovative hexagonal Closed-Loop Coil (CLC) and a set of solenoids, can generate magnetic fields up to 50% higher, enabling Nb-Ti wires to be used in the 4th-generation 45 GHz ECRIS. However, the fabrication of the CLC is the most challenging due to the complicated winding route and shape, the hard rectangular Nb-Ti superconducting wire, the small bending radius, and so on. A pre-over-bending approach and a set of unique fixtures and tools were developed to ensure successful coil winding. Also, the assembly and cooling of such efficient and compact magnets are particularly challenging due to the small radial gap between CLC and solenoids, as well as the tight operating temperature margin. To address these challenges, a structure was developed that combines a three-section radially split solenoid mandrel with a series of interference-fit reinforcement rings. This paper presents the MARS structure; the CLC winding fixtures, tools, and procedures; the solenoid mandrel and coil winding; the magnet impregnation; the cold mass assembly; and the cryostat design.

Speaker: Lianrong Xu

31 ECR Ion Sources at TRIUMF: Status and Future Developments

Electron Cyclotron Resonance (ECR) ion sources have been a cornerstone of ion beam production at TRIUMF for many years. ECR ion sources support a broad range of research programs through the delivery of a diverse suite of stable isotope beams from the “Supernanogan” at the Off-Line Ion Sources (OLIS) facility, and through the Charge State Booster (CSB) which promotes radioactive ion beams (RIB) to highly charged states for post-acceleration. Together, the OLIS Supernanogan and the ISAC CSB deliver reliable, high-quality ion beams for a diverse experimental program at TRIUMF’s existing ISAC (Isotope Separator and ACcelerator) facility, and for the upcoming ARIEL (Advanced Rare IsotopE Laboratory) experimental program.

Presented here is an overview of the status and capabilities of ECR systems at TRIUMF. This work highlights operational capabilities, delivered ion species and intensities, recent source advancements, and looks forward to a roadmap outlining planned hardware upgrades, diagnostic improvements and other longer-term research and development initiatives to enhance source performance. These developments illustrate ongoing efforts to expand beam availability and higher intensities to meet the growing needs of the research community.

Speaker: Christopher Griffin (TRIUMF)

32 Effect of Ceramic on Beam Extraction from 2.45 GHz ECR ion source

Ion source extraction modelling is commonly performed using IBSIMU, which couples non-linear sheath equations with a Poisson solver and self-consistently includes particle space charge. This approach has been widely applied using measured or fitted plasma parameters. In some ion sources, the extraction lens uses of boron nitride (BN) liners, which can enhance plasma density through electron donation. As a dielectric, BN modifies the electric potential distribution, potentially altering extraction optics in ways not captured by standard models. In this work, we investigate the impact of ceramic extraction lenses on ion beam formation. Plasma parameters are obtained via optimization by fitting simulations to experimental data. Using these parameters, we study how variations in plasma potential influence beam properties and compare trends with experiment.

Speaker: Nicolas Savard (Columbia College)

33 INSTALLATION AND STARTUP OF AN 18 GHz ECRIS FOR HIGHLY CHARGED METALLIC IONS AND GASES

This poster presents the technical improvements and experimental
characterisation of a hybrid superconducting
18GHZ Electron Cyclotron Resonance Ion Source (ECRIS)
manufactured by Pantechnik. Since the last one manufactured
in 2011, the source has undergone significant upgrades
to enhance its performance and reliability for heavy ion
beam production. Key improvements include optimisation
of the magnetic confinement system, aiming to increase the
production of highly charged ions while maintaining stable
operation at high RF power levels. An extensive experimental
campaign is currently underway at Pantechnik’s facilities
to characterise the source performance on a selection of ions
(N, Al, Ar, Au, Pb) and the goal of demonstrating stable
Xe28+ and Ta36+ beams.

Speaker: Ambra Morana (Pantechnik)

34 MACHINE LEARNING – DRIVEN OPTIMIZATION OF POSITIVE ION BEAMS ON THE LUTEX IRRADIATION FACILITY

LUTEX (Ligne pour UTilisateurs EXternes) is a high performance irradiation facility providing the world’s largest testing area (400 × 700 $mm^2$). It delivers light-ion beams with very high fluxes at 300 keV/u (∼5000km/s) for H+ up to 4×$10^{9}$ protons/$cm^2$/s. This enables rapid reproduction of extreme exposure conditions and allows for short time qualification of a material lifetime. For comparison,a typical solar storm reaches only 3keV/u (∼600km/s) and 0.2 protons/$cm^2$/s.
Operating a continuous accelerator such as LUTEX requires achieving beam stability conditions on energy and current over a long period of time tailored to experimental needs. The difficulty resides in the change of a large number of input parameters, in their nonlinear interactions and in the variability of irradiation conditions.
Pantechnik is developing a Machine Learning model designed to facilitate beam tuning, to optimize beam quality,and to predict parameters required for production of continuous beam. The model exploits data collected from plasma generation, extraction, transport, separation, and dose measurements to learn the relationship between machine settings and resulting beam performances. After data preprocessing and feature extraction, several approaches, including Bayesian optimization and nonlinear regression methods, will be benchmarked to predict and optimize the beam current as a function of operating parameters.

Speaker: Antoine Breteaux (École Nationale Supérieure d'Ingénieurs de Caen)

35 Microwave Technologies for Plasma Heating in the 88-Inch Cyclotron ECR Ion Sources

The Electron Cyclotron Resonance (ECR) ion sources at the 88-Inch Cyclotron have integrated several established microwave technologies to meet increasing plasma-heating requirements. This work reviews the vacuum electron devices employed at the facility, including klystrons, traveling-wave tubes, and gyrotrons for ECR plasma heating. Although solid-state amplifiers continue to advance, vacuum electron devices remain the preferred technology for multi-kilowatt continuous-wave microwave generation because of their higher available output power, greater efficiency, and superior tolerance to reflected power and plasma-induced load variations. Operational experience demonstrates that these technologies provide the stability and robustness required for reliable production of high-current and high-charge-state ion beams.

Speaker: Michel Kireeff Covo (Lawrence Berkeley National Laboratory)

36 Observation of Non-Synchronized Afterglow Pulses and Beam Characterization on SEISM

SEISM (Sixty-gigahertz Ion Source using Megawatt magnets) is a 60 GHz electron-cyclotron-resonance ion source that achieved in 2014 a record pulsed multicharged-ion current density of about 1 A/cm$^{2}$. Operation resumed in 2021 after upgrades to the beam line, and several experimental campaigns were performed to reproduce the conditions that previously enabled such high extracted currents.

Following the failure of the 60 GHz gyrotron in 2024, the setup was adapted to operate at 18 GHz with a new aluminum plasma chamber manufactured by additive techniques. This new microwave system, capable of both CW and pulsed operation, enabled renewed investigations of SEISM plasmas as well as emittance measurements using a pepperpot diagnostic.

Recent measurements revealed the presence of non-synchronized afterglow pulses, so far observed exclusively on SEISM. Although still under investigation, this phenomenon appears promising for advancing our understanding of CUSP-based plasma physics. Emittance scans have also identified distinct charge-state populations in argon plasmas and quantified the influence of microwave pulse duration and bias-disk voltage on beam quality and extracted current. These recent developments and results will be presented.

Speaker: Thomas Andre (Laboratoire de Physique Subatomique et de Cosmologie)

37 Preparations for Brightness Increase of the Supernanogan ECRIS at TRIUMF’s ISAC Facility Using Machine Learning

Automated tuning is an area of active development at Rare Isotope Beam (RIB) facilities worldwide. Machine development tests at TRIUMF's ISAC (Isotope Separator and ACcelerator) facility have shown that automation can be achieved using combinations of simulation and machine learning models, categorizing tuning elements into those modeled by physics simulations and those addressing unknown deviations from that model.

This project aims to optimize ion beam extraction from the ECRIS "Supernanogan" source at TRIUMF-ISAC's Off-Line Ion Sources (OLIS) facility. We develop a new comprehensive simulation of plasma generation and the ion extraction system, alongside an optimization algorithm to maximize beam quality. A planned upgrade to a modern triode optics system necessitates this new model. By establishing a strong foundation for understanding beam formation, the model becomes the basis for a Bayesian optimization (BO) control algorithm: it provides good starting points and defines constraints on parameter-space exploration to ensure safety, whether expert-informed, simulation-informed, or model-learned.

Optimization will first address beam current transmission through a new collimator, translating into maximized beam brightness. A comprehensive variation of source parameters, including microwave heating power and gas pressure, will then follow.

Speaker: Alexander Katrusiak (TRIUMF)

38 Recent Advances in High Temperature Oven Technology for Heavy Metal Ion Beam Production at Facility for Rare Isotope Beams (FRIB)

At the Facility for Rare Isotope Beams (FRIB), inductively heated High Temperature Ovens (HTOs) have been developed to provide stable and reliable production of solid ion beams from the High-Power Electron Cyclotron Resonance (HPECR) ion source. Building upon previously reported HTO developments, recent efforts have focused on supporting future FRIB operations with increased beam power and on developing new species of solid beams, including molybdenum, thorium, platinum, and uranium.
Several improvements have been implemented to enhance HTO performance under extreme operating conditions. Different susceptor materials have been investigated through simulations, offline testing, and operation on the ion source. The results indicate that tantalum and molybdenum susceptors exhibit limited compatibility with the high-magnetic-field ECR plasma environment, while tungsten and rhenium-tungsten alloy susceptors demonstrate superior stability and reliability.
Additionly, a redesigned oven structure has been developed to improve thermal distribution in the oven assembly, resulting in enhanced heating efficiency and improved utilization of isotopic materials. These improvements contribute to significantly reduced material consumption. The upgraded HTO has successfully operated at temperatures exceeding 2200 °C and has demonstrated the production of refractory metal ion beams. Detailed design improvements, simulation studies, and experimental results will be presented and discussed.

Speaker: Haoyu Cheng (Facility for Rare Isotope Beams)

39 Simulations of the ECR-based charge breeder efficiency under varying injected beam conditions

This work reports a numerical investigation of the efficiency of an ECR-based charge breeder as a function of injected beam parameters. Combining particle-tracking with a realistic plasma-target model, simulations evaluate the effects of transverse emittance and longitudinal energy spread on the optimum injection conditions and the consequent breeding efficiency. The simulations use the modelled beam through the 1+ injection beam line installed at the LPSC test bench in Grenoble with variable energy spread and emittance as input, and then take into account electrostatic deceleration due to a realistic plasma potential profile, elastic Coulomb collisions and ionizations in a comprehensive description of the charge breeding process. The presented work supports optimization of ECR-based charge breeders for radioactive ion beam facilities and other applications requiring high charge-state production, by suggesting practical guidelines for on optimum 1+ beam manipulation.

Speaker: Carmelo Sebastiano Gallo (Istituto Nazionale di Fisica Nucleare)

40 Studying plasma instabilities in an ECRIS using optical diagnostics

The UK Science and Technology Facilities Council (STFC) and iThemba Laboratory for Accelerator Based Sciences (LABS) have developed an optical emission diagnostic system for monitoring ion sources. A particular interest in this work is probing the stability of the plasma of an Electron Cyclotron Resonance Ion Source (ECRIS) non-invasively. The newly developed diagnostic system, based on thermoelectrically-cooled Multi-Pixel Photon Counters (MMPCs) and a CCD spectrometer, allows for the plasma to be studied in both wavelength- and time-resolved modes, monitoring several band-pass filtered emission lines simultaneously. This enables known plasma phenomena such as plasma instabilities to be studied in greater detail. Recently the emission lines of various ion species of interest were measured using the JYFL 14 GHz ECRIS. This measurement allowed identification of the filters required to probe the emission lines that are most sensitive to the plasma parameters. For example, probing the emission lines of the singlet and triplet systems of He-I (neutrals) as well as He-II (He+ ions) can reveal the effect of plasma instabilities on the cold electron population, inaccessible via electron spectroscopy or x-ray/bremsstrahlung diagnostics. This contribution describes the experimental setup and the line-ratio method, and presents some preliminary results.

Speaker: Moenir Sakieldien (iThemba LABS)

41 The status of ECR ion source for the new PARTIH project at GSI facility

The new project, based on a reversed HITRAP (Highly charged Ion Trap) facility to a PARTIH (PARTicle Injector Hitrap), will provide the first ion beam for the commissioning of the Facility for Antiproton and Ion Research (FAIR) and at the same time deliver a sufficient beam intensity of carbon ions to meet some basic experimental requirements already in 2027. To achieve this, accelerator cavities with existing radio-frequency-quadrupole (RFQ) infrastructure together with an interdigital H-type linac including a triplet and steerer, as well as, a room temperature Electron Cyclotron Resonance (ECR) ion source, will be installed within the transfer line of the SIS18 synchrotron during a limited installation period.
The ECR ion source is required to produce a 12C5+ in order to stay within the constraint of the accelerator of a maximum mass to charge ratio m/q < 2.6, with an intensity of tens of µAs and an injection energy 6 keV/u at the RFQ entrance. The current status of the ECR ion source, the newly developed low-energy beam transport (LEBT) system, and the associated accelerator infrastructure designed to support the PARTIH project to deliver a first beam to the FAIR facility are presented here.

Speaker: Rustam Berezov (GSI Helmholtz Centre for Heavy Ion Research)

42 Upgrade of PhoenixV3 and production of stable ions beams for S3

GANIL has been producing many stable beams for nearly 40 years. Constant progress has been made in terms of intensity, stability and reliability. The intensity for some stable metallic beams now exceeds or approaches the pµA level at an energy up to 95 MeV/u: Since 2019, the beam times available on the cyclotron accelerators have been reduced in favour of the commissioning of the SPIRAL2 linear accelerator.

The Spiral 2 facility is a superconducting linear accelerator producing high intensity of stable beams for S3 (Super Separator Spectrometer) and NFS (Neutrons For Science).
The ECRIS Phoenix V3, which is connected at linear accelerator, will produce the Q/A=1/3 stable beams for S3.
This ECRIS has been designed by LPSC Grenoble and has been connected at the SPIRAL 2’s low energy line in 2019.
This presentation highlights the upgrade of Phoenix V3 since 2019 and the development of several stable beams for S3.

Speaker: frederic LEMAGNEN (Grand Accélérateur National d'Ions Lourds)

Wednesday 30 September

01 LBNL Welcome

WEA: Oral session

43 Electron Cyclotron Resonance Dissociator Demonstrator for the Project 8 Experiment

Project 8, a neutrino mass experiment, employs the novel frequency technique of cyclotron radiation emission spectroscopy (CRES) to perform a model independent measurement of neutrino mass via tritium beta decay. Our pioneering experiment will consist of an atomic tritium beamline that dissociates molecular tritium, surface cools atoms with an accommodator, evaporatively cools and slows atoms, and traps them in a CRES resonant cavity to advance towards our sensitivity goal of 40 meV/c^2 for our final neutrino mass measurement.

At Indiana University, we are prototyping an electron cyclotron resonance (ECR) dissociator that uses a tunable 1 kW 2.45 GHz RF generator and a static magnetic field to ignite a hydrogen plasma in an aluminum resonant cavity operating in the TE111 mode. Our ECR source is designed to produce a high atomic flux (~10^19 atoms/second) at room temperature. This talk will present the engineering development, gas diagnostics, and spectroscopy data from our hydrogen plasma.

Speaker: Manjinder Oueslati (Indiana University Bloomington)

44 ECR Electrostatic Thruster: From ECRIS to ECRET

Electric Propulsion (EP) is a type of space propulsion that can reduce the cost of orbital service. There are different types of electric thruster, including ECR Electrostatic Thruster (ECRET), which uses ECR to generate plasma. Ions are then accelerated in outer space by electric force to develop the thrust: $T=\dot{m}v$, where $\dot{m}$ and $v$ are the ion flow rate and their exhaust velocity. This concept is from ECRIS**, capable of producing high currents of multiply charged ions. The high ion ejection velocities result in interesting EP performance, in particular in terms of specific impulse: $I_{sp}=g_0^{-1}v$, where $g_0$ is the gravitational acceleration. This work describes initial tests of an ECRIS operating as an ECRET.

The results were obtained using a 10 GHz Microgan ECRIS supplied with argon or xenon. The plasma was ignited at an RF power of up to 25 W, and ions were extracted using a voltage of up to 15 kV. A magnetic dipole and a Faraday cup were used to characterize the beam. These measurements and the reported parameters allowed the computation of thruster performance.

A low thrust of ~10 µN for ~100 µA and a very high specific impulse of ~10 ks are obtained. The gas appears to be consumed efficiently, but this ECRIS needs to be adapted to develop more thrust by extracting more current. The use of multiply charged ions implies a greater power requirement, a limitation in EP. The total efficiency is discussed, and possible adaptations are then presented

Speaker: Romain BELLET (Université Paris-Saclay, CNRS/IN2P3, IJCLab, Osmos X)

45 Revolutionizing Nuclear Physics with Neutrons: Electron Cyclotron Resonance Ion Source Technology and the Neutron Target Facility at LANSCE

At the Los Alamos Neutron Science Center (LANSCE), we are pursuing the capability to directly measure neutron reaction cross sections on unstable isotopes and improve our predictive modeling abilities for mission science and nuclear astrophysics. A Neutron Target Facility (NTF) will address these nuclear data needs. The NTF will employ a radioactive ion beam storage ring coupled to a thermal neutron field to induce reactions in inverse kinematics. This neutron target concept will be validated by the ongoing Neutron Target Demonstrator (NTD) experiment at LANSCE that is leveraging a pulsed, high-intensity electron cyclotron resonance (ECR) ion source for heavy ion beam production and interaction with a first-ever neutron target. Design and operational features of this Low-Energy Heavy Ion Source (LEHIS) will be presented along with recent beam testing results. The NTD experiment operations and execution plan will also be described. In closing, considerations of ECR ion source technology for the future NTF and its science impact will be discussed.

Speaker: Andrew Cooper (Los Alamos National Laboratory)

10:40 Break

WEB: Oral session

46 Research on the Production of mA-level High-Intensity Pulsed Ion Beams

The production of mA-level high-intensity, highly charged pulsed ion beams is a key technology for the development of advanced heavy-ion synchrotrons. By utilizing the afterglow mode of an ECR ion source (ECRIS), pulsed ion beams can be produced with peak intensities several times higher than those in the conventional continuous-wave (CW) mode, and the application of a pulsed biased disk voltage in the afterglow mode can further enhance the pulsed beam intensity. In this paper, an experimental study combining a pulsed biased disk with the afterglow mode was conducted on the SECRAL-IV ion source. A Bi³¹⁺ ion beam with a peak intensity of 1 mA was obtained and successfully delivered to the downstream accelerator, enabling the accumulated ion beam in the HIAF-BRing to reach 3.166 × 10¹⁰ particles per pulse (ppp).

Speaker: Lixuan Li (Institute of Modern Physics, Chinese Academy of Sciences)

47 Sumitomo Presentation

48 Isoflex Presentation

49 Mechanism of High-Efficiency Microwave Heating in ECR Ion Sources Using Vlasov Launchers

Microwave heating efficiency is a pivotal factor in improving electron cyclotron resonance ion source (ECRIS) performance. Recently, Vlasov launchers have been applied in third-generation ECRISs and have yielded significant performance enhancements; however, the underlying physical mechanisms remain to be fully understood. In this study, we developed a plasma dynamics simulation model to investigate the mechanism of this high-efficiency microwave heating. The results show that microwave power absorption in the front axial region strongly affects the plasma density distribution, particularly the spatial distribution of warm electrons. By reshaping this power absorption profile, the Vlasov launcher increases the warm-electron density, deepening the plasma potential and thereby enhancing both ion confinement and the ionization rate, which ultimately improves the overall performance of the ion source.

Speaker: Xinyu Wang (Institute of Modern Physics, Chinese Academy of Sciences)

02 Conference Photo

12:30 Lunch

03 LBNL Tour

05 Social Dinner

Thursday 1 October

THA: Oral session

50 First Results from the Nusano 60 kV ECR Ion Source and Low-Energy Beam Transport System

Nusano’s proprietary electron cyclotron resonance ion source has been commissioned with a magnetic Low Energy Beam Transport (LEBT) system operating at an extraction voltage of up to 60 kV. The LEBT has been used to diagnose, characterize, transport, and tune the beam extracted from the ion source. Initial results from deuteron beam operation will be presented, including measured beam transmission across the LEBT and characterization of the electrostatic chopper located upstream of the Radio-Frequency Quadrupole (RFQ). A standalone beam-tuning station design has also enabled rapid validation of beam through the RFQ. These measurements inform data-driven improvements to the operation and design of future ion source and LEBT upgrades.

Speaker: Ruoyu Fang (Nusano)

51 Advances in beam line diagnostics for the VENUS ion source

An essential part of electron cyclotron resonance (ECR) ion source optimization and operation is the analysis of extracted ion beams. Reliable and accurate beam line analysis of the multi-species ion beam provides a vital indicator of ECR operation. In this work, we present new developments and improvements to beam line diagnostic tools developed for the VENUS ion source at Lawrence Berkeley National Lab, including rapid charge-state-distribution measurements and emittance scans. Our focus on making measurements fast and available with a single button press has made them a part of routine operation for both source and accelerator operators. Operator-facing tools are written in Python 3 and leverage graphical interfaces for user interaction and remote databases for data storage, retrieval, and collaboration. This work discusses how using large language models (LLMs) aided the rapid development of interface design without compromising the scientific basis for the tools. By using LLMs to do much of the initial interface work and design iterations, more time was available to develop better analysis methodologies. The tools and methods presented can be adapted or used directly to diagnose the performance and beam of various ion sources.

Speaker: Jessica Rehak (Lawrence Berkeley National Laboratory)

52 Learning Hidden Plasma and Transport States from Operational Data in the FRIB ECR Ion Source

This contribution presents initial efforts towards a machine-learning framework for estimating latent ECR source states from operational data collected at the Facility for Rare Isotope Beams (FRIB). The approach combines time-series measurements from source controls, beam transport elements, and current diagnostics to infer hidden variables associated with plasma conditions, ion production, and beam transport.
The work is motivated by the limited availability of direct plasma diagnostics during routine operation, and by an earlier study of a baseline predictive model, which showed that predictive accuracy alone does not guarantee physically meaningful internal representations. Building on this finding, we are designing a hierarchical latent-state architecture that mirrors the physical signal path from source controls through plasma formation, extraction, and transport, with each stage supervised, where possible, by intermediate diagnostic measurements, so that the learned representations remain tied to source physics rather than incidental correlations.
This work is an early step toward an operational digital twin of the FRIB ECR ion source. We present the motivating diagnostic findings, the proposed architecture, and open questions ahead of implementation, with an eye toward future applications such as fault diagnosis, performance prediction, and AI-assisted tuning.

Speaker: Luciano Silvestri (Facility for Rare Isotope Beams)

53 On the effective injection of neutral material into an ECR plasma

There is agreement in the field that highly-charged ions are more prevalent on axis in an electron cyclotron resonance (ECR) ion source. Since the net radial diffusion is outward, it would seem to follow that injecting material into the ECR plasma (especially expensive, low-abundance material) nearer the axis would be advantageous. In this paper we give a progress report on our attempts and efforts injecting low-abundance, neutral materials into the center of the plasma and suggest how these results might be used to improve the efficiency of material usage.

Speaker: Damon Todd (Lawrence Berkeley National Laboratory)

11:00 Break

04 Geller Prize and Closing Remarks

12:30 Lunch

06 Excursion