This paper presents the enhancement of photon beam position stability at the Siam Photon Source (SPS) synchrotron through a real-time feedback control system incorporating a fault-tolerant control (FTC) algorithm. The system utilizes Photon Beam Position Monitor (pBPM) measurements within a global orbit feedback loop to minimize beam position fluctuations. The FTC algorithm plays a critical...
The Synchrotron Light Research Institute (SLRI) in Thailand aims to operate a 6-MeV electron linear accelerator for irradiation, supporting various agricultural and industrial applications. This study presents a method for measuring electron beam energy using the existing dipole magnet in the beamline, originally designed for scanning X-rays on samples through a scan horn. An aluminum sheet...
Sudden beam loss (SBL) is one of the obstacles to improving the luminosity of SuperKEKB. SBL cause damage to collimators and other accelerator components, QCS quench, and large background to the Belle II detector. It also causes beam abort and prevents the accumulation of high currents. Therefore, it is an important issue to investigate and resolve the causes of SBL events. In order to...
The Korea-4GSR (4th Generation Synchrotron Radiation Source) is under construction since 2021 to be a state-of-the-art research facility requiring exceptional stability for its electron beam to ensure high-quality experimental data. Ground vibrations originating from both natural and artificial sources can significantly impact the stability of critical components, particularly the accelerator...
The Super Tau-Charm Facility (STCF), a third-generation electron-positron collider operating in the tau-charm energy region, will be subject to mechanical disturbances and ground vibrations, which can lead to beam-beam misalignments at the interaction point (IP). Such misalignments degrade luminosity and shorten beam lifetime. To maintain an optimum beam collision condition, the development of...
The experiment to measure the Electric Dipole Moment (EDM) of Francium (Fr) is in progress by Center for Nuclear Study (CNS), UTokyo. Fr is produced via a nuclear fusion reaction by bombarding a gold target with oxygen-18 beam, requiring a beam intensity of 18 eμA or higher. However, the transport efficiency of the current beam line decreases to 66 % when the beam intensity exceeds 10 eμA. To...
The CSNS RCS (Rapid Cycling Synchrotron) is a proton accelerator designed to achieve a target beam energy of 1.6 GeV, with a typical operating intensity of 140 kW, which is expected to increase to 500 kW after the CSNS II upgrade. However, a significant current instability has been observed during the 100 kW beam operation. To mitigate this instability, techniques such as operational tuning...
As part of the new Proton Improvement Plan (PIP-II), Fermilab is undertaking the development of a new 800 MeV, 2 mA H- superconducting RF linac to replace its present normal conducting 400 MeV linac. The PIP-II linac consists of a series of superconducting RF cryomodules from 2.1 MeV to 800 MeV. To limit the potential damage to the superconducting RF cavities, PIP-II will utilize non-invasive...
The Siam Photon Source (SPS) is a 1.2-GeV synchrotron facility in Thailand, operated by the Synchrotron Light Research Institute (SLRI), providing synchrotron radiation for various applications to the user community. The SPS injector linac generates 40-MeV electron bunches, which are then transported to the booster synchrotron via the Low-Energy Beam Transport line (LBT). To ensure effective...
We have developed a highly sensitive beam profile monitor, the High-Gain Residual Gas Ionization Profile Monitor (HGRGIPM). The HGRGIPM detects electrons ionized by the proton beam in residual gas, which are guided by electric fields to a phosphor screen. The fluorescence is collected by an optical system. RGIPMs have proven to be powerful diagnostic tools for high-intensity beams because they...
The increasing demands for high-resolution beam diagnostics necessitate advanced simulation tools capable of modeling complex wave-optics phenomena. We present an optical simulation toolkit based on the angular spectrum propagation method, validated through comparisons with SRW. For synchrotron radiation interferometer simulations, the toolkit demonstrates excellent agreement with SRW results,...
Materials with a minimal interaction with particle beams are widely used in accelerators in interceptive instruments such as screens, secondary emission grids and wire scanners. Material damage limits are already exceeded in energy frontier and high brightness machines.
A new generation of ‘low density’ materials with nano-structures are becoming available at scales of interest for use in...
Accurate measurement of photon beam position and profile is crucial for beamline users to achieve precise alignment and efficient utilization of the desired photon beam. In low-emittance storage rings, however, the power density of the photon beam has increased, making it challenging for conventional profile monitors such as wire scanners and scintillating screens to withstand the high power...
To enhance the performance of next-generation X-ray Free Electron Lasers (XFELs), it is crucial to produce high-quality electron beams with low emittance, particularly for attaining emittances below 0.2 mm.mrad for 100 pC bunch charges. This study introduces an emittance measurement method using an orthogonal dual-slit technique, aimed at enhancing measurement efficiency and achieving the...
The objective of this work is to assess the accuracy of measurements made by the Electron Beam Profile Scanner (EBPS), which captures the trajectory of an electron beam with and without a proton beam present. The proton beam induces deflection in the electron beam, which is influenced by proton charges.
For high-resolution images, the probe beam needs to be of high intensity, small diameter,...
We recently introduced a novel interferometric method inspired by radio astronomy, utilizing a Non-Redundant Aperture (NRA) mask with self-calibration to fully characterize the two dimensional transverse shape of electron beams from a single-shot interferogram.
This paper reports the latest advancements in this technique, including a new data analysis approach based on closure amplitudes,...
A Gas Sheet Beam Profile Monitor (GSBPM) was designed and developed for the Integrable Optics Test Accelerator (IOTA) at Fermilab. IOTA will receive 2.5 MeV protons, with an average beam current of 8 mA. Before implementation at IOTA, the GSBPM performance was tested at the Crocker Nuclear Laboratory cyclotron at UC Davis, CA. The cyclotron proton energy produces at the range from 60-5.45 MeV...
In proton FLASH therapy the beam monitoring is crucial to ensure the conformal dose deposition to the tumour and effective Organ at Risk (OAR) sparing. A non- invasive real time beam monitoring improves the efficacy as the dose is delivered in shorter time scales. To achieve this, gas-jet based Ionization Profile Monitor (IPM) is developed with potential capability towards real time beam...
A new orbit feedback system has been introduced to the PF-ring, a synchrotron radiation source at KEK, starting from the third operation period of FY2024. The new system is built with state-of-the-art digital signal processing circuits based on the MicroTCA.4 standard. The stored beam’s closed orbit distortion (COD) is measured at a 10 kHz rate using the circuits matched to the number of BPMs,...
As one of the most valuable noninvasive profile monitors in proton and heavy ion facilities, 6 Ionization Profile Monitors (IPM) have been installed in two synchrotrons of High Intensity heavy ion Accelerator Facility (HIAF). Among them, 5 IPMs are equipped with the Micro Channel Plates (MCPs) 、Phosphor screen (P46) and camera acquisition. The goal is to obtain the large envelop with good...
Beam Halo Monitoring (BHM) is essential for high-intensity accelerators like the HL-LHC. Carbon Nanotube (CNT) wires offer a promising alternative to traditional carbon fibre scanners due to their lower density, improved thermal properties, and reduced beam interaction. This work evaluates the performance of CNT wires in beam halo diagnostics, focusing on their energy and intensity range,...
Linear wire scanners are essential instruments for beam profile measurements in the Large Hadron Collider (LHC) at CERN. The current scanners installed in the machine have shown reliability and performance limitations in recent years. This work presents the development and validation of a bespoke motion system for the next-generation LHC wire scanners. The design replaces vacuum bellows with a...
The Alternating Gradient Synchrotron (AGS) at Brookhaven National Lab is equipped with two types of Ionization Profile Monitors (IPMs): ion-collecting and electron-collecting. Ion-collecting IPMs are susceptible to significant distortions in the measured beam size due to the space charge of the passing beam. Conversely, electron-collecting IPMs are much less affected but can only be operated...
A model-based optimal control approach has been developed for the slow orbit feedback (SOFB) system to enhance orbit stability in the Siam Photon Source (SPS) storage ring. The control strategy utilizes a linear quadratic regulator (LQR) based on a multi-input, multi-output (MIMO) state-space model of the linear SPS storage ring, derived through system identification using MATLAB and SIMULINK....
Transverse beam diagnostics with standard imaging techniques represent a challenge for next-generation accelerators and colliders due to the extremely small beam sizes, and X-ray interferometry offers an interesting method to overcome this challenge. In this regard, the X-ray Heterodyne Near Field Speckles (X-HNFS) technique has successfully been used to resolve few-micrometer beam sizes and...
An ECR microwave H+ source has been built at the HUN-REN EK-CER that targets medium current (20mA) and 35 keV beam energy in continuous or pulsed mode (0.1-10ms @ 0.01-25Hz) and low normalized beam emittance (< 1 π mm.mrad).
A new gas jet-based diagnostic system installed on the proton source provides non-invasive beam profile measurement * and allows a novel way for emittance evaluation with...
As part of our search for radiation-hard techniques for beam profile monitoring, we have conducted a novel experiment using microstructured optical fibres, which are known for their extremely high radiation tolerance, filled with scintillation gases, which are also inherently radiation hard. We tested this new technique at the CLEAR accelerator at CERN, demonstrating its potential for beam...
Optical Transition Radiation (OTR) is a widely used diagnostic technique in accelerator particle beam applications, providing high-resolution beam profile measurements. This work focuses on the development and implementation of OTR-based beam profile monitors for the transfer lines at the Advanced Light Source (ALS) and its upgrade (ALS-U), with the goal of enabling real-time, online beam...
The Synchrotron Light Research Institute (SLRI) operates the SPS-I facility located in Nakhon Ratchasima, Thailand, which provides synchrotron light for various scientific and industrial applications. The linac injector, serving as the primary injector, is responsible for electron beam bunching and acceleration to 40 MeV, after which the beam is transported to the booster ring via the...
Real-time beam monitoring is essential for enhancing the efficacy and reliability of radiotherapy. FLASH radiotherapy has shown a strong potential in improving treatment effectiveness by delivering doses at ultrahigh dose rates (>40 Gy/s). Beam monitoring at FLASH is challenging, as existing devices like Ionization chambers face saturation. We are developing an all-optical monitor for...
PEPITES*
is an ultra-thin and wide dynamic range charged particle beam profiler. Its signal uses secondary electron emission, effective with only O(10 nm) of matter and highly linear with beam intensity. Thin film techniques are used for the sensitive area, enabling multiple monitor variants. Typical electrodes are membranes with 50 nm thick gold strips or fully metallized. Several systems...
This paper investigates the signal characteristics of Titanium, Tungsten, and Carbon materials used in a secondary electron emission grid setup at CERN's North Area. Periodic scans were conducted to reconstruct beam profiles and assess the performance of these materials, configured as wires and bands, under slow-extracted 400 GeV protons. The study aims to inform the design and optimization of...
In the framework of SOLEIL-II, the project of SOLEIL's storage ring upgrade towards lower emittances, preliminary studies were performed to pinpoint the resolution limits of the exisiting pinhole cameras.
However, while reducing the vertical emittance from the SOLEIL's nominal 50 pm.rad value to 8 pm.rad, unexpected filaments were observed in the image plane of the pinhole cameras, severely...
The beam halo can contribute to beam losses in accelerators and is very difficult to measure. With an increase in beam intensity following the PIP-II upgrade at Fermilab, the beam losses are expected to be higher with some coming from beam halo. Therefore, it is important to measure the sources of beam halo to minimize the beam losses. A modified Halo Monitor developed by J-PARC will be...
In the China Spallation Neutron Source (CSNS), an Ion Profile Monitor (IPM) was installed in the Rapid Cycling Synchrotron (RCS) to address challenges in measuring strong-current beam profiles and enable real-time monitoring. This study focuses on the preliminary analysis of IPM data signals, aiming to accurately extract critical beam information from the signals. Residual gas components in...
A non-invasive photon-detection beam profile monitor using a gas sheet, named the gas sheet monitor, has been developed. Our gas sheet is formed based on rarefied gas dynamics. To obtain a beam profile quantitatively, we have also devised a beam reconstruction method with a response function measurement method. These methods gave a 2-D beam profile of a high-intensity 3 MeV beam at the J-PARC...
AA new harp has been installed in the Ring To Target Beam line (RTBT) section of Spallation Neutron Source. The harp is made of two planes with 32 titanium 50 micron wide wires each plane. The narrow, low-Z wires versus the 100-micron tungsten wires of the original harp, are to minimize the beam scattering. This harp will be both a backup and a complement to the existing harp further...
We present a robust simulation framework for using Optical Synchrotron Radiation (OSR) as a non-invasive tool to extract the transverse emittance of relativistic electron beams in advanced accelerator facilities. As next-generation accelerators target higher brightness and lower emittance, conventional diagnostics may fall short. OSR, coupled with an optimized optical transport system, offers...
In the Karlsruhe Research Accelerator (KARA), electron beams of up to 200 mA are stored with an energy of 2.5 GeV, while injection is performed at 500 MeV. At the injection energy, the beam life time and the injection efficiency depend largely on Touschek scattering. As a counter-measure, the beam size can be enlarged transversally by an excitiing modulation, e.g. applied via a strip-line....
High-brightness, megahertz-rate electron sources are a crucial component of future light sources, including the Linac Coherent Light Source II High Energy project, or the high-duty-cycle upgrade of the European X-ray Free-Electron Laser. The Helmholtz-Zentrum Dresden-Rossendorf has employed a superconducting radio-frequency (SRF) gun as one of its CW electron sources for user operation at ELBE...
We present an upgraded beam monitoring system designed for use in high-radiation environments where conventional imaging solutions rapidly degrade. In the presented device the radiation-sensitive P47 phosphor screen of the previous system* is replaced with a radiation-hard Chromox ceramic scintillator and relocates the CMOS camera outside the irradiation zone by transmitting the optical signal...
Shifting RF phases is a common task in particular at particle accelerators. Which RF frequencies need to be shifted is highly facility dependent, which demands a wide range phase shifter. The phase shifter presented in this contribution consists of a custom board, that includes a high-performance quadrature modulator, voltage regulators and an 16-bit digital-to-analogue converter that offers...