The vertical beam size measurement was carried out at BEPCII using a phase grating and an absorption grating based on the Talbot effect. Due to the partial coherence of the source, coherence length can be calculated by measuring the visibility decay of interferograms recorded at different distances behind gratings. The vertical beam size of 68.19±2μm was obtained based on the relationship between coherence length and source size. A comparison of the vertical emittance derived from grating Talbot method and synchrotron radiation visible light interferometer method was presented to evaluate the method. The vertical emittances from two methods are 1.41nm·rad and 1.40nm·rad respectively. The 0.1% difference indicates the grating Talbot method for beam size measurement is reliable. This technique has great potential in small beam size measurement in the fourth-generation synchrotron radiation light source, considering its small diffraction limitation and simple experimental setups.

Obtaining the complete distribution of a beam in high-dimensional phase space is crucial for predicting and controlling beam evolution. Based on the theory of maximum entropy tomography, we developed an algorithm for reconstructing the four-dimensional (4D) transverse phase space distribution. Our algorithm can take any number of 2D linear projections as constraints, and iteratively converges to the unique numerical solution which is the maximum-entropy distribution satisfying the constraints. Having verified the algorithm with simulation experiments, we plan to use it to conduct 4D phase space tomography in the MEBT and HEBT of the heavy ion linac CAFe II.

The electron accelerator S-DALINAC can be operated in conventional acceleration (CA) and energy recovery (ER) modes. In an ER mode, electrons pass the main linear accelerator (LINAC) twice as often compared to the corresponding CA mode: following the acceleration, the electrons are decelerated to return kinetic energy to the electromagnetic fields inside the cavities of the main LINAC. The recovered energy is recycled during the acceleration of subsequent electrons. However, as a result of the deceleration, the electromagnetic fields are impacted. Thus, the fields and consequently the beam properties after acceleration in ER mode differ from those in CA mode. To compare the beam properties after acceleration present in both modes, a non-destructive diagnostic system is necessary since otherwise the ER mode would be interrupted. For this reason, wire scanners were build and used to measure beam properties in the two-turn CA and the two-turn ER mode. Details on the wire scanners and the measurements are presented.

To convert weak current signals into voltage pulse signals proportionally, a 128-channel readout electronics system is developed. The front-end analogue circuits of this readout electronics system are designed based on the Charge to Frequency Converter (CFC) circuit structure, and the back-end digital board processes the voltage pulse signals. After the performance test in the laboratory and the beam test in PREF, This system can proportionally convert currents from 1 pA to 1 μA into voltage pulse signals with an input dynamic range of 120 dB. The maximum nonlinear error does not exceed ±10%, and the system’s resolution is less than 100 fA. The isolation between the adjacent channels is lower than -114 dB. The system is used not only for beam profile monitoring, but also for the flatness, symmetries and scanning uniformity measurements of slow-extraction beams. The system is of great value in the field of weak beam profile measurements.

In response to CERN's need for alternative imaging solutions of scintillating screens due to the discontinuation of radiation-hardened VIDICON tubes, the single large-core multimode fiber (MMF) has been identified as a potential medium to transmit image signals to a CMOS camera situated away from radiation-prone areas. However, significant challenges in image distortion at the fiber's output end complicate the reconstruction of the original beam distribution. To address this, a novel machine learning-based approach was introduced that utilizes a deep convolutional encoder-regressor network. It first compresses the fiber image into a latent space. Subsequently, a fully connected regression network directly estimates the beam parameters, such as centroids and widths, from the encoder output without the need to reconstruct the detailed image. This contribution will showcase an end-to-end system capable of estimating transverse beam parameters from the MMF output speckle patterns. Offering a safe, camera-preserving solution for beam imaging in high-radiation environments.

The classical double-aperture interferometry using the visible part of the synchrotron radiation has been used in accelerators for beamsize measurements since the late 90s. However, this technique provides the beam size projection only in the direction given by the two aperture centers (i.e. only the horizontal or vertical direction). To fully characterize the transverse electron beam ellipse, given by the two semi-axis of the ellipse and its tilt angle, the double-aperture system could be rotated in a process that can take few minutes. Instead, using radio-astronomy techniques, this paper shows a new interferometric method with several apertures by which a full 2d transverse beam characterization is done in real-time.

Several experiments were done to measure the transverse beam size at the NCD ALBA beamline using the Heterodyne Near Field Speckles (HNFS) technique. Inside the FCC collaboration, it was decided to move these experiments to the ALBA Front End 21, where currently an x-ray pinhole camera is working since 2021. The goal is that the two measurement techniques can work alternatively and measure the electron beamsize of the same source point, so that a direct comparison between both techniques can be done. This paper reports the SRW simulations performed in order to investigate the feasibility of the HNFS experiments at this new location. In particular, it focuses on the effect of the dipole radiation and the design of the high energy and high bandwidth monochromator requirements.

The feasibility of X-ray Fresnel diffractometry to measure small beam sizes beyond the resolution of X-ray pinhole cameras is studied for the case of Diamond Light Source. After the Diamond-II upgrade, beam sizes as small as 4 µm are anticipated and are not resolvable by the X-ray pinhole cameras, which are the workhorse for beam size, emittance, and energy spread measurements. X-ray Fresnel diffractometry employs a single slit with an optimised width, producing a double lobe diffraction pattern. The visibility of this double lobe intensity distribution relates to the beam size and promises micron-scale beam size measurement. Numerical studies and simulations have been conducted to assess the feasibility of diffractometry for Diamond Light Source. The parameters for the experimental setup have been determined and preliminary experimental results are presented. Challenges and improvements for achieving this measurement for Diamond-II are discussed.

The Insertion Device (ID) photon beam of a synchrotron can be contaminated with radiation from upstream and downstream bending magnets, causing position measurement errors in blade-type monitors. Beamlines of the low emittance storage ring are particularly sensitive to photon beam position variations, requiring more accurate measurements. To address this, we designed an ionization profile monitor to non-destructively measure the profile and position of the white undulator beam at Korea-4GSR without contamination. Leveraging the relatively large active area of readout devices suitable for small emittance beams we have designed a 1:1 mapping field to defocus photo-ions. Given that the defocusing field can induce errors due to vertical position, we propose a calibration method and validate it using particle tracking simulation.

Achieving sustainable beam operation in high-power accelerators requires careful control and minimization of halo-particle-induced beam loss. To accomplish this, it is important to have a clear understanding of the halo-particle distribution. While state-of-the-art instruments can achieve a dynamic range of ~10^6 with counting readout schemes, a novel fluorescence wire scanner combined with a conventional metal wire has recently been proposed and demonstrated at CSNS. This new approach has achieved a sensitivity at the single-particle level and a dynamic range of over 10^8. A 100x1x0.15 mm^3 Chromox fluorescence wire has been prepared at CSNS, which has demonstrated excellent light yield and radiation hardness. By capturing fluorescence images with a CMOS camera in a dark environment, a new record dynamic range of about 6x10^8 has been achieved. Continue efforts on optimizing the fluorescence wire, observation system, and sensor hold promise for further improvements in dynamic range and sensitivity.

A pepper-pot diagnostic device was developed to accurately and robustly retrieve particle distribution in horizontal and vertical phase spaces by single-shot emittance measurements. Two masks that differ in both composition and manufacturing method were fabricated: one made of phosphor bronze by an optical lithography process and another made of stainless steel (SUS) by laser cutting. Scanning electron microscope (SEM) measurements of the two masks revealed that the former is superior in terms of regularity and shape of the mask holes and is therefore more suitable to use. A new image-processing algorithm, cluster noise removal method, was developed which improves the resolution of the phase-space distribution measurements over traditional methods. The results show that the diagnostics can robustly and reliably retrieve the four-dimensional (4-D) phase-space distribution of ion beams with a single-shot measurement.

To ensure patient safety, treatment efficacy, and facility efficiency, a full online characterisation of the charged particle beam is required for every ion beam therapy facility. Current dosimetry methods offer limited information or are invasive to the beam, asking for the development of in-vivo dosimetry solutions. The QUASAR Group, based at Cockcroft Institute in the UK, has been developing non-invasive beam monitor for medical accelerators since 2015. Detailed transverse beam profile monitoring is the first step towards in-vivo dosimetry. The current monitor applies a supersonic beam gas curtain, interacting with a charged particle beam to then exploit the resulting impact ionization to record the transverse beam profile. A prototype monitor was tested at Dalton Cumbrian Facility’s pelletron accelerator for proof-of-concept beam measurements in summer 2023. The measurements were carried out for different beam energies, sizes and intensities and with both, proton and carbon ion beams. This contribution presents the monitor design and functioning principle, results from the experimental campaign, and planned upgrades to achieve real-time, non-invasive dosimetry.

Quantifying the difference between two beam distributions in high-dimensional phase space is crucial for interpreting experimental or simulation results. This study aims to analyze and compare several common statistical divergences that quantify the differences in high-dimensional distributions, and to determine which of them are suitable for beam physics applications. We tested these divergences with common kinds of initial distributions by computing how the difference values vary when the mismatch factor and emittance change, between the same and different kinds of distributions. These results, along with similar comparisons after extended beam transport, provided guidance on the use and choice of statistical divergences for beam phase space distributions.

This paper presents a bunch-by-bunch profile measurement system, which includes an optical imaging frontend, a multi-channel photomultiplier tube (MAPMT) for photoelectric conversion, and a high-sampling-rate oscilloscope for data recording. The system is capable of measuring the transverse positions and sizes of each bunch in the storage ring during the beam availability period of the Hefei Light Source II (HLS-II). By finely processing the collected data, the system can effectively recognize the dynamic characteristics of the beams and monitor the performance of the light source. Here, the paper elaborates on the system’s design principles, optical layout and system configuration. It also introduces the program workflow of data processing, along with an analysis of the corresponding measurement errors.

The 60 MeV Proton Radiation Effects Facility (PREF) spent nearly 1 month at the commissioning phase, during which the multi-strip ionization chamber (MIC) at the experimental terminal offered the core parameters, beam spot, scanning area, scanning uniformity, beam flux. However, the projection distribution provided by the MIC loses some information, such as the flux and the uniformity in a selected area less than the scanning area. This paper used a method of two-dimensional reconstruction to provide a 2D uniformity of selected area. Revealing the trace of the pencil beam at a sampling rate of 10 kHz.

An X-Ray pinhole camera beamline has been installed recently at SESAME storage ring as a very beneficial non-destructive tool, used to characterize the electron beam size and behaviour. The design of the beamline is kept as simple as possible with a modification on the copper absorber to provide a sufficient flux of X-ray proper for imaging. The beamline is under operation now and used for the measurement of beam size, emittance, coupling in the ring, and detection of beam instabilities. This paper describes the design details, simulations and measurement results obtained during the beamline com-missioning.

Visible light range of Synchrotron radiation is a versa-tile diagnostics tool for accelerator studies and measurements. SESAME’s storage ring has a dedicated diagnostics visible light beamline from 6.5-degree beam port of bending magnet source point. The beamline will host in future a time-correlated single photon counting unit to measure the bunch filling pattern, fast gated camera and a streak camera for longitudinal diagnostics. Recently, the beamline has been extended to be operational from out-side the tunnel (dedicated hutch) to allow more flexible studies with direct source imaging and a double-slit interferometry for beam size measurement and study trans-verse instabilities. In this paper we give an overview of the design of the beamline, modifications and present first results.

The beam transverse profile is very essential in the beam diagnostics of a high intensity proton accelerator. A Residual Gas Ionization Profile Monitor (IPM) has been developed and implemented as a non-destructive diagnostic tool at the LRBT of CSNS. The design specifics of the IPM and presents initial measurements conducted in ion collecting mode are discussed in this paper. Big challenges arose during the initial experimental period, especially the honey comb. A series of planned experiments are outlined to address these challenges in future IPM developments.

The applications of proton beams require precise diagnosis of their properties including spectrum and spatial distribution. Distinct from the case of traditional accelerators, limited online detectors are available for laser-driven proton beams with high transient fluence, somewhat impeding the progress in this field. This paper presents an online proton spectrometer, named Scintillation Fiber Cube Proton Spectrometer (SFCPS), which can diagnose proton beams with sub-millimeter (~500 um) spatial resolution and wide fluence range. The SFCPS offers an energy range of approximately 6~93 MeV with an energy resolution of 0.5% at 80 MeV, as calibrated. We demonstrated the SFCPS's ability to reconstruct the 2D energy spectrum of parallel proton beams with uneven spatial distributions. Further discussion and analysis reveal that the SFCPS's lower detection threshold for proton beams is approximately 1×10^5 p/cm2.

The Siberian Ring Radiation Source (SKIF) is an upcoming 4th-generation SR source under construction in Novosibirsk, Russia. The designed beam emittance for SKIF is 75 pm-rad, which corresponds to a beam size of 6 micrometers at the observation point within the dipole magnet. The transverse beam dimensions are essential parameters for tuning and reliable operation of the facility. The SKIF diagnostic suite includes a double-slit interferometer operating in the ultraviolet region of the spectrum. This device's spatial resolution should be sufficient to measure the radial size of the beam to an accuracy of 10 percent. These diagnostics will be used during the commissioning of SKIF and afterwards. Although an additional source of information on beam dimensions and dynamics would be desirable for assurance, taking into account the record designed value of beam emittance. The application of X-ray optics and the Kirkpatrick-Baez focusing system seem to be the most suitable options. The article discusses the project of this system, which will acquire X-rays from a SKIF dipole magnet. Simulations of the heat load on the mirrors, means of compensation of thermo-induced surface distortion (thermo-bump) and the spatial resolution of the KB system are described. The choice of scintillator screens, expected temporal resolution, and sensitivity of the diagnostics are discussed as well.

In order to reduce the projected transverse beam emittance, a solenoid is usually used at normal conducting as well as superconducting radio frequency (SRF) photoinjectors. At the ELBE SRF Gun-II, a superconducting solenoid is located inside the gun´s cryomodule about 0.1 m far from the end of the gun cavity. The solenoid has a longitudinal magnetic field on the axis with a Gaussian-like shape and an effective length of 0.042 m. To determine the beam aberration due to the anomalous, weak quadrupole fields of the solenoid, we measured and analyzed the multipole fields of the solenoid. In this paper, two different multipole magnetic field analysis methods are presented. We also calculated the effect of these fields on the beam emittance. Based on these studies, a group of quadrupole correctors has been installed downstream in the beamline. A comparison of the experimental findings for quadrupole field correction and simulation will be given. For beams with relatively large diameters, the spherical aberrations of the solenoid can increase the emittance significantly. For that reason, an improved solenoid design meets the mechanical and cryogenic demands.

To enhance the performance of the next generation of X-ray free electron lasers (XFEL), it is essential to produce a high quality electron beam with a low emittance, for instance, below 0.2 mm-mrad for a 100 pC bunch charge. In order to demonstrate the fundamental techniques required for future FEL facilities, a C-band photoinjector test facility has been constructed aligning with the Southern Advanced Photon Source (SAPS) pre-research project. An emittancemeter based on the consecutive double-slit-scan concept has been proposed and designed for determining such small emittance. This paper presents the further optimization of the primary parameters of this emittancemeter employing numerical simulations in the presence of the measured motion accuracy and the expected observation resolution.

The beam power is lifted up to 500 kW for the phase II of the China Spallation Neutron Source (CSNS-II) project, which is five times the power of CSNS-I. At the CSNS, the neutron beams are generated by the spallation reaction of 1.6-GeV protons striking on a tungsten target. The multiwire profile monitor (MWPM) in front of the proton beam window is the only instrument for long-term monitoring of proton beam distribution when the protons are delivered to the spallation target. The wire interval of the target MWPM of CSNS-I is 7 mm, which is slightly sparse for beam profile measurements during the beam operation in recent years. To ensure the precisely monitoring and provide accurate signal for the Machine Protection System (MPS) when the beam is abnormal, an upgraded design was proposed and implemented. The design mainly employs the Printed Circuit Board (PCB) technique to route the signal originated from the tungsten wires. Four bias planes comprised of tungsten wires are added to mitigate the crosstalk effect brought about by stray electrons and enhance the secondary emission effect. The minimal wire interval of present design is 2 mm and the whole equipment is more compact compared with the previous one due to the PCB scheme. This paper will detail the design and manufacturing of the CSNS target MWPM.

The FNAL accelerator complex has been upgrading in increasing beam intensity and beam quality. A new beam halo diagnostic device is required in the beam transport line between booster and Recycler. For this purpose, it was decided to introduce the wide dynamic range monitor technique that was developed in 2012 and has been in operation at the J-PARC beam transport line. The device is a two-dimensional beam profile monitor, and it has a dynamic range of approximately six digits of magnitude by using of Optical Transition Radiation and fluorescence screens. Eliminating harmful beam halos is the most important technique for high-intensity proton accelerators. Therefore, beam halo diagnosis is indispensable and becomes more and more important. New FNAL device has been manufactured in a collaboration between J-PARC and FNAL as a part of U.S.-Japan Science and Technology Cooperation Program in High Energy Physics. The equipment will be manufactured at J-PARC and will be shipped to FNAL in 2025. We designed the device to satisfy FNAL specifications: the beam energy, intensity, and size. Currently, most of the equipments are under construction. The large-aperture optical system has been completed and its optical characteristics are being evaluated at J-PARC. We have been also investigating measurement methods corresponding to FNAL bunch trains. This paper reports on the current status of these developments.

The Nanogate-38 gated camera with a temporal resolution of 60 nanoseconds was used to measure the transverse beam dimensions in the BEP booster and the VEPP-2000 electron-positron collider. The camera was used in combination with a double-slit interferometer to measure the vertical beam size and with projection optics to construct a transverse beam profile in single-turn mode. Some beam characteristics were measured, such as decoherence time, radiation damping time and fast attenuation time. The purpose of these experiments was to investigate the possibility of using this camera to measure the transverse dimensions of the beam and its emittance, as well as to conduct experiments on accelerator physics at the SKIF synchrotron radiation source.

For diagnostics of the different bunch types at the BESSY II electron-storage ring, a streak camera and a fast-gated ICCD camera have been installed at two neighbouring beamlines*, both of which are powered by visible light from the same dipole magnet. This contribution is focused on the ICCD camera and its first applications. After an improvement regarding the ICCD repetition rate, the maximum illumination rate exceeds now the BESSY II revolution frequency of 1.25 MHz. Furthermore, we have improved the optical light-transfer system and characterized the optical magnification, the spatial resolution and time resolution of the system. Initial measurements have been restricted to direct bunch-resolved imaging of the 2-dimensional transverse shapes of different types of bunches. Specifically, the Pulse Picking by Resonant Excitation (PPRE\**) bunch is investigated in more detail. This bunch is horizontally broadened by a quasi-resonant incoherent perturbation *\*\* and leads to pseudo single-bunch radiation within the complex multi-bunch fill-pattern at the BESSY II storage ring.

Beam Gas Ionization monitors have been in operational use in the CERN PS for two years now, and they were installed in the SPS this year. An overview of the operating principal of the instruments is presented, followed by an update on their development. The mechanical design has been simplified and the Timepix3 devices are now mounted individually for easier assembly and maintenance. Reliability and availability have been improved with a new radiation-hard readout, using the GBTx and bPOL12 devices. Performance has been improved with a SoC Back-End making good use of both the FPGA and the Processing System. We have worked to improve the calibration of the instruments, equalization can now be performed in-situ and we have a procedure to calibrate the response between the four detectors. This paper also presents some example results from the instruments and describes our plans for future developments.

The measurement of the longitudinal phase space at the end of FERMI linac is one of the most important characterization of the electron beam properties prior to delivery to the FEL lines. It is performed using an RF-deflecting cavity in conjunction with a dipole to spread the beam in time and energy. The beam transverse distribution is then measure with a multiscreen. The original multiscreen installed in 2009 had a large FOV with a 45deg YAG orientation and 1.5MPx camera. An upgrade has been devised to improve resolution, frame rate and robustness to COTR contamination. The upgrade design is based on a COTR suppressing geometry, a dispersion minimizing incidence angle, a double mirror vacuum optical layout and a Scheimpflug camera geometry. The optical distortion has been characterized by using a precision checkerboard target and automatic Matlab nodes detection. This leads to a transformation matrix that is applied at the image server level to the raw image to remove the trapezoidal distortion. The detector is 8 Mpx 10 Gbit/s CMOS camera fiber coupled to the image sever and capable of full frame 50Hz acquisition.

Accurate measurement of flux rate is essential in heavy-ion single event effects tests, but it presents significant challenges for monitoring low energy (5~10 MeV/u) and low intensity (less than 1E6 /s) heavy-ion beams. In this paper, we propose a novel detector that enables real-time monitoring of flux rate by simultaneously measuring the beam intensity and profile using secondary electrons on both the front and back surfaces of thin foils. The confinement of sec-ondary electrons through electric and magnetic fields is achieved, with CST simulation has been utilized to validate the method. This approach offers several ad-vantages over conventional methods, including high space and time resolution, reduced mass thickness, and multi-parameter measurement capability.

Non-invasive and turn-by-turn beam transverse profile monitoring is essential for the tunning and operating CSNS 1.6 GeV Rapid Cyclic Synchrotron. A residual gas Ionization Profile Monitor (IPM) was designed and installed in RCS for horizontal beam profile measurement. However, several challenges related to electromagnetic interference (EMI), vacuum, and MCP operation in the IPM were identified. The EMI is induced by the beam itself and further accelerator components. An improved Faraday cage was implemented to counteract the EMI issues. In order to achieve the desired MCP gain, a suitable pull-down resistor was incorporated into the MCP power supply circuit. After these improvements, the IPM was commissioned successfully. This paper will describe the challenges of IPM and early beam commissioning results.

The SKIF, a fourth-generation synchrotron radiation source is being constructed in Russia. This installation has an ultra-low emittance, allowing for high beam intensity in various scientific and technological fields. A crucial aspect of SKIF is its availability of diagnostic instruments that measure the beam transverse dimensions. This will allow for minimizing the emittance during operation and comparing it with a calculated value. This comparison is critical for determining whether the physical setup meets the design specifications. In addition to measuring the transverse dimensions of the beam, it is also important to observe the behavior of the longitudinal profile and measure its parameters with good accuracy. Since the calculated emittance of 75 mrad corresponds to the beam sizes of less than 8 microns at the radiation output sites, a diagnostic complex was developed as part of the working project, including a beam size monitor based on a double-slit interferometer. Observation and measurement of the longitudinal distribution of the beam will be carried out using mutually complementary devices, such as a streak camera and electron-optical dissector.

The Rare Isotope Accelerator Complex for ON-line Experiments (RAON) is a facility designed to produce rare isotope beams using the ISOL and IF methods. RAON has a variety of diagnostic devices to measure beam characteristics. Among them, emittance is an important parameter in determining beam characteristics. RAON was applied the Multi-wire scan and Quadrupole scan methods to measure emittance using a wire scanner. These methods of measurement was confirmed through beam generation and transmission simulation at Python. Afterwards, in the beam commissioning, the beam size were measured by 3 wire scanners installed in the MEBT section and the emittance were calculated from the Multi-wire scan and Quadrupole scan methods. In this poster, we presents simulation results and Argon beam emittance measurement results.

Although there is no clear definition of beam halo in particle accelerators, it is generally regarded as particles outside of the beam core with an intensity level of less than 10-5 or 10-6 of the peaks. In high-intensity, high-power hadron accelerators, the presence of halo particles may cause emittance growth and beam loss, difficulties in beam control and collimation, increase the noise of detectors, and cause activation or even damage to accelerator components. To understand the halo dynamics, experimental studies are essential, but the required detection techniques are often too limited and do not meet the required high dynamic range. In this contribution, a supersonic gas curtain-based profile monitor is considered for beam halo measurement in high-intensity, high-power hadron accelerators. This monitor is based on the beam gas curtain (BGC) monitor, successfully used in the Large Hadron Collider. Instead of a broad curtain with uniform density, a new concept with two shorter curtain segments which can be adapted to the shape of the beam core and aim at the halo particles only is applied. The monitor design and operating principle will be presented, and the anticipated integration time, signal intensity and dynamic range will be discussed, as well as opportunities for increasing the sensitivity by incorporating micro-channel plates or the Timepix detector.

In the past year, the wire scanner at SXFEL is upgraded to a new firmware. Unlike the previous version, where a target frame is equipped with tungsten wires in three directions, the new system uses horizontal and vertical independent scanning methods. The beam loss detector adopts plastic scintillator fiber, and the PMT module is also designed with a Raspberry PI for dynamic signal conditioning. The detailed design is described in this paper.

To address non-standard Gaussian beam spot pro-files in injectors, this paper proposes a fitting algo-rithm based on Gaussian, the newly introduced Gener-alized Gaussian Type and Skewed Gaussian Type dis-tributions. These distributions are specifically de-signed to better fit non-Gaussian and asymmetric beam spots by automatically selecting the most suitable model. Validation using beam spot images from the YAG screen after the electron gun in the Hefei Light Source II (HLS-II) injector demonstrates that the Gen-eralized Gaussian Type is effective for fitting sharp or broad profiles, while the Skewed Gaussian Type is well-suited for handling asymmetry. Compared to tra-ditional methods, the proposed algorithm improves fitting accuracy and adaptability, providing a practical solution for complex beam measurement challenges.

More than 4 Ionization Profile Monitors (IPM) have been mounted in HIRFL, which play an important role in the beam optics optimization, electron cooling research, and ion-electron recombination study so on since 2016. To meet the profile needs of HIAF project with multiple beam species and high dynamic challenges, mainly two kinds of IPM structure have been chosen. At first, 5 IPMs equipped with the Micro Channel Plates (MCPs) 、Phosphor screen (P46) and camera acquisition have been deployed in Booster Ring (Num. 3) and Spectrometer Ring (Num. 2), which use discrete electrodes for precisely high voltage supplying and can achieve a good spatial resolution around 50 µm. There is also another IPM designed without a P46 and camera for the electron-photon conversion and capture, but a ceramic anode and the fast multi-channel electronics instead. The purpose is to measure a fast turn by turn profile with a least 64 MHz sampling rate for machine studies. Some new features and experiments have also been performed at IMP, like using an IPM for transverse emittance measurements. A compact IPM with one cage measuring horizontal and vertical profiles has also been built and tested, which shows good results under a constraint magnet filed. And a new prototype based on the ionization products captured by a microstrip line or coaxial 50 Ω anode is proposed to measure bunch shapes. It’s for sure that the ionization mechanism or yields can be explored more values in the beam instrumentation.

A Long Radial Probe is a device used to measure the transverse beam profile in a cyclotron along its radius. The current iteration of the probe was installed in the PSI Main Ring Cyclotron in 2022. After a successful start, the probe encountered issues due to strong coupling with RF fields leaking from the cavities, which resulted in the breakage of the carbon fibers. A series of corrective measures were attempted, but the initial results were inconclusive. This paper discusses the challenges faced and presents the experiments and thermal calculations that provided insights into the RF heating issue.

To serve the needs of the High Luminosity (HL) LHC, a consolidation of the beam wire scanner has been initiated. The instrument is a crucial tool for measuring the transverse beam profile by moving a thin carbon wire across the beam. It can only withstand a fraction of the LHC's nominal beam intensity but provides a reference to calibrate other instruments that operate non-invasively at higher beam intensities. Since the start of the LHC, the scanners have provided hundreds of thousands of measurements, but the design has technical limitations that need to be addressed to provide the required reliability and performance for the HL runs. The initial consolidation phase involved testing the injector's acquisition and control electronics in the LHC to assess its suitability for the specific beam conditions. As part of this process, we updated the mechatronic and motion controller. Beam test campaign has revealed higher performance w.r.t the existing system and a higher adaptability to varying beam conditions. Simultaneously, we are developing a novel actuator that uses a permanent magnets-based coupling replacing the standard bellows and long arm that limits the performance and induces vibrations. Before testing this new concept with beam, we have developed a calibration bench to evaluate the mechanism’s precision and accuracy of the wire position determination. This contribution presents the 2023 beam and laboratory tests as well as the electromechanical developments.

Sensitive cameras are frequently operated to record low-light processes such as Beam Induced Fluorescence or optical transition radiation for transverse profile determination. We compared four cameras based on different principles: Firstly, we investigated an Image Intensifier equipped with a double MCP (producer ProxiVision); secondly, an electron-multiplied CCD (emCCD Teledyne Princeton Instruments ProEm+:512B); and, thirdly, sCMOS cameras (producer PCO.edge4.2bi and Teledyne Kinetix 22). LEDs generate light pulses within a wavelength range of 385 to 500 nm and a duration of 0.03 to 8 ms to vary the photon flux. Moreover, the spatial resolution is compared. The image intensifier is the most sensitive camera type and provides very low noise; however, the method provides only a limited spatial resolution. The investigated emCCD camera has a comparable sensitivity but provides a better spatial resolution. The sCMOS cameras provide a factor of about 5 to 10 lower sensitivity depending on wavelength. A quantitative comparison of signal-to-noise ratios and statical fluctuations for several wavelengths will be presented.

High Energy Photon Source (HEPS) is a 6 GeV dif-fraction limited storage ring light source. An ultralow emittance of ~34 pm·rad is designed with a multiple-bend achromat lattice at storage ring. The transverse beam sizes at the dipoles will be less than 10 µm. In order to measure such small beam sizes in both directions, an X-ray beam diagnostic beamline is designed with bend-ing magnet as source point. X-ray pinhole imaging and KB mirror imaging are used compatibly and comparably to capture beam image. A visible light beam diagnostic beamline is designed to measure bunch length with streak camera. During the first phase storage ring commissioning time, both diagnostic beamlines captured the first light.

The Iranian Light Source Facility (ILSF) plays a crucial role in advancing accelerator science and applications. In this study, we explore innovative techniques for precise beam profile monitoring, focusing on two complementary methods: Incoherent Cherenkov Diffraction Radiation (ChDR) and scintillating screens. Incoherent ChDR occurs when a charged particle passes through a dielectric medium with a velocity exceeding the phase velocity of light in that medium. This phenomenon leads to the emission of electromagnetic radiation in the form of a cone. Our investigation focuses on incoherent ChDR as a powerful tool for beam position diagnostics. By analyzing the angular distribution of ChDR photons, we extract valuable information about the transverse position of the electron bunch. Our simulations demonstrate the feasibility of ChDR-based diagnostics at ILSF. We discuss optimal radiator materials, geometries, and detection strategies. in addition, We also present our findings on scintillating screen calibration, spatial resolution, and dynamic range. We believe that our research significantly contributes to the development of robust and efficient beam diagnostics at the storage ring of ILSF. By investigating Cherenkov Diffraction Radiation (ChDR) and utilizing radiation from scintillating screens, we enhance accelerator performance and facilitate future experiments.

Thin objects in the form of wires, foils or strips are often used as targets in various instruments that measure beam parameters or for other purposes. They usually cause only small beam perturbations and suffer from relatively low temperature increases. The beam induces the emission of secondary electrons, which are usually the source of the measured signal. In high brightness beams, the targets can reach high temperatures, which lead to thermionic current emission. Also, a small amount of delta electrons is emitted, which has a negligible effect on the emitted current but affects the beam heating. These three types of electrons have different properties and influence the measured signal as well as the temperature evolution of the target. This paper discusses how the signal is generated by the escaping electrons, how bunch field affects this signal and how the target temperature depends on the electron emission.

The Beam Gas Curtain (BGC) monitor was installed in the beam one of the Large Hadron Collider (LHC) during Long Shutdown 2 (LS2) and the Year-End Technical Stop (YETS) 2022. The monitor detects the fluorescence signal generated due to the interaction between the charged particle beams in the LHC and the neon atoms in the supersonic gas curtain. This provides 2D images of the primary beam. In the 2023 run, it was demonstrated that transverse beam profile measurement for both, proton beam and lead ion beams in the LHC is possible across injection, energy ramp-up and top energy operation. The BGC has shown the potential to be an operational instrument and efforts to integrate the monitor into the main machine control system are being undertaken. In this contribution, we will present measurement results and discuss the operational experience including observed gas loads to the LHC, observed impact on beam losses and demonstrated resolution of the monitor. Finally, we will also discuss future plans for the continued optimization of this monitor and the installation of a second monitor into beam two.