Optical Cherenkov Radiation (ChR) is a well-known type of radiation, which is utilized in different fields of physics such as charged particle detection or generation of intense THz radiation. It is also widely used in beam diagnostics, for instance, in beam loss monitors or for bunch length measurements. In addition, it is of potential interest for transverse beam profile diagnostics as an...
China Spallation Neutron Source (CSNS) accelerator complex will employ a new superconducting accelerating section to achieve high beam power. To protect the superconducting cavity from contamination, the second phase of the CSNS superconducting linac section will adopt laser stripping technology for transverse distribution measurements of the negative hydrogen beam at nine stations. In 2024, a...
At Diamond, it was previously observed that the response of the beam changes with mode number when excited by the transverse multi-bunch feedback (TMBF). This study presents the results of various experimental campaigns carried out to investigate the behaviour of tune-sweep waveforms for a variety of stored beam conditions and TMBF settings. We demonstrate that it is unlikely that wakefields...
The High Energy Photon Source (HEPS) is the fourth-generation synchrotron light source with a beam energy of 6 GeV, developed by the Institute of High Energy Physics. As a essential partment of the HEPS, The Fast Orbit Feedback (FOFB) systemhas been developed to maintain the beam orbit stability. In this work, a neural network-based algrithm has been designed and developed to replace the...
This study presents the design, specifications, and experimental validation of the Allison scanner installed at the injector of the 100 MeV proton accelerator operated by the Korea Multi-purpose Accelerator Complex (KOMAC). The Allison scanner was developed to enable precise characterization of the proton beam’s phase space at the injector stage. Detailed design parameters and operational...
During the pre-research phase of China Spallation Neutron Source (CSNS) upgrade project (CSNS-II), in order to conduct beam commissioning of the Radio Frequency Quadrupole (RFQ) under high-intensity beam conditions, The structure of the last-stage wire scanner of the Medium Energy Beam Transport (MEBT) was innovatively modified. This modification not only added a Beam Stop but also...
Diamond-II will require two types of stripline kickers during normal operation: the kicker actuators for the transverse multibunch feedback system; and the injection stripline kickers which enable transparent injection. Both are very similar in design as they need to kick individual bunches without disturbing the following bunches. The main difference is the voltage requirements. The feedback...
After the success of 80 MeV negative hydrogen beam profile measurement based on laser wire monitor, in order to further realize the beam emissivity measurement, an emissivity measurement system combining the laser wire monitor and LGAD (low-Gain Avalanche Diode) sensor has been designed. The idea is to use the LGAD sensor to detect and reconstruct the H0 distribution, combined with the...
This work presents the development and experimental validation of a control system for synchrotron X-ray beam stabilization. A laboratory-scale replica of a beamline was constructed using an analog oscilloscope to emulate beam dynamics. Electrical actuation was implemented via deflection plates, while disturbances were introduced using an electromagnet. Beam position monitoring was performed...
In order to test the Standard Model through a precision measurement of the muon anomalous magnetic moment, a 212 MeV muon accelerator is being developed and constructed for the J-PARC muon g−2/EDM experiment. During the early stage of commissioning, the number of muons per pulse could be fewer than 100, necessitating a highly sensitive monitor. In addition, muon identification must be...
A wire Scanner profile Monitor (WSM) has been developed for the demonstration ring of Fixed Field Alternating gradient (FFA) accelerator, called FETS-FFA. From previous studies, Carbon Nano Tube (CNT) wire is selected for the FETS-FFA WSM, durable for the heat damage of low-energy proton beams on the FETS-FFA test ring (3-12 MeV). A bias voltage, applied to the measuring wires, is required to...
In order to improve our transverse diagnostic tools, two new pinhole
beamlines will be designed. The pinhole arrays will be in air for easier
maintenance: this will result in a significant loss of X-Ray photons
when passing through the vacuum window. To overcome this issue, the
option to directly illuminate a CCD/CMOS camera with X-Ray radiation
without prior conversion into visible...
Transverse beam profile monitoring is essential for safe and efficient accelerator operation. In high-radiation environments such as beam dumps, cameras degrade rapidly. To address this, a single multimode fiber (MMF) transmission system was previously tested to transport scintillation light from a screen to a remote camera. Because multiple guided modes are excited and coupled during...
In radiotherapy, treatment beams require precise margins to ensure the preservation of surrounding healthy tissue. Clinical studies have shown that to mitigate range deviations of the Bragg peak, safety margins of typically less than 5\% around the target volume are employed. Consequently, real-time or online diagnostic techniques should be designed to minimize beam perturbation to the...
The Diamond-II upgrade will enhance the performance of the Diamond Light Source synchrotron, including improved beam stability by the Fast Orbit Feedback system. Achieving the targeted closed-loop bandwidth of 1 kHz necessitates an open-loop actuator bandwidth of approximately 10 kHz, which presents significant design challenges for the corrector magnet vacuum vessel. Additionally, subsystems...
The Low Energy RHIC Electron Cooler (LEReC), the world’s first RF-based non-magnetized electron cooler successfully provided cooling of gold ions at γ-factors 4.1 and 4.9 during RHIC Runs 2019-2021, substantially increasing RHIC luminosity. Since then, LEReC has been routinely used for numerous cooling studies. Development of trajectory and energy feedbacks for electron beam was an important...
Transverse beam profile diagnostics constitute a critical component in free-electron laser (FEL) operation and optimization. As a standard diagnostic tool, optical transition radiation (OTR) has been widely adopted in FEL facilities. However, as the bunch longitudinal length below 500 fs, the OTR method becomes significantly affected by coherent effects. This paper presents a systematic...
The SOLARIS synchrotron light source has commissioned a transverse bunch-by-bunch feedback system designed to suppress coupled-bunch instabilities and serve as a diagnostic tool for accelerator studies. The system was successfully installed and integrated with the existing infrastructure, including timing and control systems. After a series of commissioning steps, it was brought into operation...
Beam imaging systems are integral parts of beam instru-
mentation at CERN, measuring the shape, size, and position
of particle beams in accelerators. Following the worldwide
phasing out of analog cameras and vidicon tubes (which the
system was initially based on and still partially uses), part
of the ongoing consolidation program involves developing a
new camera system based on digital...
A laser wire monitor has bean developed at the China Spallation Neutron Source (CSNS).The monitor utilizes a 1064 nm laser source to measure the horizontal and vertical profiles of a negative hydrogen ion (H-) beam with an energy of 80 MeV in the injection zone. This paper describes the design of the laser optical path layout and the characterization of the transport performance. The...
A low energy experimental bench called LEEx-B is being developed at IPHC-CNRS of Strasbourg, France. The bench is composed of a CS+ ion gun mounted on a HV platform and beams up to 25 keV are provided. The main objective of this bench is to support the advancement of beam diagnostics, including the ongoing development of the Allison-type emittance-meter. This paper presents the progress of the...
The measurement of transverse profiles of the electron beam is key to measuring and optimizing the emittance of a linear accelerator. Also, transverse profile monitors are used in conjunction with an RF deflecting structure to measure bunch length and slice emittance. An RF deflector and a profile monitor behind the undulator can furthermore be used to reconstruct the FEL pulse profile. I will...
Pinhole cameras serve as the primary diagnostic for emittance and energy spread measurements in the storage ring of Diamond Light Source. Similar pinhole cameras will be employed for the Diamond-II upgrade, to enable direct imaging of the stored beam while also allowing for the monitoring of skew, profile, position, and instabilities. The emittance and coupling are calculated from the acquired...
The Beam Gas Curtain (BGC) is an instrument for transverse diagnostics in operation at the Large Hadron Collider (LHC). The transverse beam profile is obtained by imaging the fluorescence light resulting from the interaction between the beam and a thin supersonic neon gas jet. This technique can provide minimally invasive and absolute measurements of LHC high-intensity beams, throughout the...
SuperKEKB is a high luminosity electron-positron collider that aims to achieve an instantaneous luminosity ten times higher than the present world luminosity record by SuperKEKB itself. However, stable operation is hampered by a phenomenon known as Sudden Beam Loss (SBL), where beam instability occurs within tens of microseconds, resulting in significant beam loss and triggering a beam abort....
SIRIUS, the Brazilian 4th generation synchrotron light source, has been in operation since 2020. Over time, insertion devices (IDs) are expected to populate its straight sections. To supress edge effects from undulators and support overall beam stability, a feedforward correction system is currently available through EPICS layer for the first installed ID. However, performance could be...
Space charge effect was considered a driving force for emittance growth in high-intensity beams. To understand it, the emittance needs to be measured. In the past, the quadruple scan was one of the simple and efficient methods to measure beam emittance, but it is difficult to apply to high-intensity beams where the space charge plays a dominant role due to the deviation from the quadratic...
The Electron Ion Collider (EIC) requires an electron cooler operating at the EIC injection energy to obtain the design proton beam emittances. A non-magnetized RF-based electron cooler, the EIC Low Energy Cooler (LEC), is currently under design. It will be operating at γ-factor 25 and will be delivering 70 mA electron current to a 170 m long cooling section (CS). To obtain required cooling an...
The CERN Beam Instrumentation group is currently investigating a radiation-hard beam profile monitor for the CERN North Area. Our main efforts are now focused on straw tubes, a type of wire chamber detector that offers the advantage of being vacuum-compatible and easily equipped with in/out motorisation. We have launched an extensive testing campaign across several CERN accelerators to...
The bunch-by-bunch feedback system is now an key function in high-current, multi-bunch storage rings to suppress coupled-bunch instability and/or to reduce the effects of injection vibration. In high-luminosity e+e- colliders such as SuperKEKB, strong beam-beam interactions occur due to collisions, which usually introduce very wide frequency response on the transverse bunch motion far out of...
NanoTerasu is a 3 GeV light source newly constructed in Sendai, Japan. The circumference is 349 m and the natural emittance is 1.1 nm rad, which is realized by a double-double-bend achromat lattice. The commissioning of the storage ring started in June 2023. The longitudinal instability was observed when the stored beam current reached 150 mA in August 2023. The temperature of RF cavity was...
We report on the development of a faster variant of the oscillating arm wire monitors (OAWM), which are in use at PSIs HIPA facility since the 1970s. It occupies little space in beam direction, which is a rare property of fast wire monitors. In first tests a wire speed of 4 m/s is reached with a stepper motor, resp. 8 m/s with servo motor.
Accurate and continuous measurement of the transverse beam profile is essential for optimizing the performance of particle accelerators. At the Large Hadron Collider (LHC), this task is performed non-invasively by the Synchrotron Radiation Telescope (BSRT). Operational since Run 2, the BSRT has undergone upgrades enhancing its reliability and performance. It operates under conditions that pose...
A beam gas curtain (BGC) monitor was installed in the LHC for continuous transverse beam profile and emittance measurement. A molecular gas curtain was injected into the LHC continuously. In this work, a pulsed gas jet operation was proposed to minimize the introduction of gas molecules to the beam line and optimize the background pressure. The study was conducted on a gas curtain beam profile...
Organic scintillators offer high sensitivity and fast response but face challenges in achieving both high spatial resolution and rapid acquisition, and are prone to radiation damage. We present a novel beam profiler based on silicon microchannels filled with scintillating resin, each individually read out by a photodiode array connected to custom microcontroller-based electronics. The...
During CERN’s Long Shutdown 2 (LS2) in 2022, the Anti-Proton Decelerator (AD) target area underwent major renovations, including a significant upgrade to its beam imaging system. The previous tube-based camera, used in a high-radiation environment, had limitations in sensitivity and resolution for continuous measurements.
The upgraded design uses an innovative in-air light-emitting screen...
