Table of contents

A dedicated R&D is ongoing for the charged particle identification system of the ALICE 3 experiment proposed for the LHC Run 5 and beyond. One of the subsystems for the high-energy charged particle identification will be a Ring-Imaging Cherenkov (RICH) detector. The possibility of integrating Cherenkov-based charged particle timing measurements is currently under study. The proposed system is based on a proximity-focusing RICH configuration including an aerogel radiator separated from a SiPM array layer by an expansion gap. A thin high-refractive index window of transparent material, acting as a second Cherenkov radiator, is glued on the SiPM array to enable time-of-flight measurements of charged particles by exploiting the yield of Cherenkov photons in the thin window. We assembled a small-scale prototype instrumented with different Hamamatsu SiPM array sensors with pitches ranging from 1 to 3 mm, readout by custom boards equipped with the front-end Petiroc 2A ASICs to measure charges and times. The primary Cherenkov radiator consisted of a 2 cm thick aerogel tile, while various window materials, including SiO₂ and MgF₂, were used as secondary Cherenkov radiators. The prototype was successfully tested in a campaign at the CERN PS T10 beam line with pions and protons. This paper summarizes the results achieved in the 2023 test beam campaign.

A rapid increase in the use of proton therapy for cancer treatment has been seen in the last decade due to its clinical advantages. Therefore, more and more patients with implants and other metallic devices will be among those who will be treated. This study experimentally examines the effect and changes in the delivered fields, using water-equivalent phantoms with and without titanium (Ti) dental implants positioned along the primary beam path. We measured in detail the composition and spectral-tracking characterization of particles generated in the plateau region of the Bragg curve towards the Sub-peak region using high-spatial resolution, spectral and time-sensitive imaging detectors with a pixelated array provided by the ASIC chip Timepix3. A 170 MeV proton beam was collimated and modulated in a polymethyl methacrylate (PMMA) block. Placing two dental implants behind the PMMA block, the radiation was measured using two pixeled detectors with silicon (Si) sensors. The Timepix3 (TPX3) detectors measured in detail particle fluxes, dose rates (DR) and linear energy transfer (LET) spectra for resolved particle types. Artificial intelligence (AI) based-trained neural networks (NN) calibrated in well-defined radiation fields were used to analyze and identify particles based on morphology and characteristic spectral-tracking response. The beam was characterized and single-particle tracks were registered and decomposed into particle-type groups. The resulting particle fluxes in both setups are resolved into three main classes of particles: i) protons, ii) electrons and photons, and iii) ions. Protons are the main particle component responsible for dose deposition. High-energy transfer particles (HETP), namely ions exhibited differences in both dosimetric aspects that were investigated: DR and particle fluxes, when the Ti implants were placed in the setup. The detailed multi-parametric information of the secondary radiation field provides a comprehensive understanding of the impact of Ti materials in proton therapy.

Picosecond-level phase determinism in timing distribution systems is a requirement for future detectors in High Energy Physics. FPGA transceivers traditionally used to propagate timing signals generally do not meet this stringent requirement, suffering from phase jumps at startup and from drifts due to temperature variations. While ad hoc solutions have been developed using FPGA features to measure and correct for phase shifts, they remain FPGA specific and therefore cannot be generalized to all types of timing links. This paper presents a study using discrete components to monitor and correct for phase drift, allowing for an implementation of a generic deterministic link.

Particle colliders operating at an increasing luminosity for High Energy Physics (HEP) experiments often present greater challenges in the design of the front-end readout circuits, especially when exploring the possibility of employing Depleted Monolithic Active Pixel Sensors (DMAPS) for timing in HEP. This paper presents a methodology for the timing performance optimization in the context of the future collider experiments. First a simplified model is presented for theoretical performance analysis and the validity is tested. Then an optimization process is done to find the best parameters regarding the trade-offs from the application requirements.

Next-generation high-energy physics experiments will employ high-granularity detectors with thousands of readout channels, necessitating the use of low-power, compact ASICs. The CAEN FrontEnd Readout System (FERS) 5200 integrates these ASICs within small, synchronizable, and distributable systems featuring both Front and Back Ends. The A5203 FERS module incorporates the recently released CERN picoTDC ASIC, enabling high-resolution timing measurements for Time of Arrival (ToA) and Time over Threshold (ToT). In this work, we analyze the performance of the A5203 unit, which has a 3.125 ps least significant bit (LSB), delivering ToA measurements with an RMS resolution of approximately 7 ps for signals of fixed amplitude, and approximately 20 ps RMS for input signals with variable amplitude over a 50 dB dynamic range over a single board. The amplitude-dependent walk effect is corrected using ToT, which, in addition to walk correction, is also utilised for signal amplitude reconstruction and background reduction. The A5203 has been successfully applied across various experimental and industrial contexts. In the concluding section of this paper, we will discuss its application within the ProVision project: a PET scanner specialised in imaging aggressive prostate cancer at an early-stage.

Designed for accelerator beam diagnostics and photon science applications, KALYPSO is a line array camera that stands out for its high-speed performance with the ability to operate at rates up to 12 Mfps in continuous readout mode while maintaining full occupancy. In this contribution, the KALYPSO system with sensor based on TI-LGAD is presented. The latest version of this system is employed as a beam diagnostic imaging sensor to measure radiation profiles of the particle beam at the KIT accelerator, KARA. The system's key features will be presented, including its linearity, sensitivity, and dynamic range.

An on-detector power distribution scheme for the High Granularity Calorimeter (HGCAL) Phase-2 upgrade of CMS is under development. This scheme is based on a heavy-copper flexible printed circuit board (FPC), allowing for an efficient use of the tight integration space, with minimal insulation overhead, excellent electrical and thermal performance and simplified integration, when compared with a wired solution. This work introduces the technology, how it allows the HGCAL challenges to be overcome, and the characterization studies. Prototypes testing are presented to validate the concept and quantify the manufacturability, electrical performance, and safety of the proposed solution.

A monolithic High Voltage CMOS (HV-CMOS) prototype, UKRI-MPW1, has been developed to further improve the radiation tolerance of this technology, which is a promising candidate for future high-energy physics experiments. UKRI-MPW1 addresses the issues of high leakage current and parasitic channels identified in its predecessor, UKRI-MPW0, by incorporating an improved chip ring structure and a custom p-shield layer. Additionally, a new pixel flavour with an NMOS-only trimming Digital-to-Analogue Converter (DAC) further improves pixel performance. This chip has demonstrated a radiation tolerance of up to 3 × 10¹⁵ n_eq/cm².

The design and simulation results of an ultra-low power, fast 10-bit Successive Approximation Register (SAR) Analog-to-Digital Converter (ADC) in CMOS 130 nm technology are presented. This ADC is an extension of an experimentally verified 10-bit SAR ADC (INL, DNL < 0.5 LSB, ENOB > 9.5), working up to 50 MSps and consuming 680 μW at 40 MSps. The goal of the present work was to add a programmable threshold for the processed input signal, to stop the conversion and thus greatly reduce power consumption in case the signal is below the threshold. The new ADC works up to around 40 MSps and consumes around 350 μW at 40 MSps for low particle occupancy.

The objective of the study is to evaluate the evolution of the performance of the new ATLAS Inner-Tracker (ITk) strip sensors as a function of radiation exposure, to ensure the proper operation of the upgraded detector during the lifetime of the High-Luminosity Large Hadron Collider (HL-LHC). Full-size ATLAS ITk Barrel Short-Strip (SS) sensors with final layout design, ATLAS18SS, have been irradiated with neutrons and gammas, to confirm the results obtained with prototypes and miniature sensors during the development phase. The irradiations cover a wide range of fluences and doses that ITk will experience, going from 1×10¹³ n_eq/cm² and 0.49 Mrad, to 1.6×10¹⁵ n_eq/cm² and 80 Mrad. The split irradiation enables a proper combination of fluence and dose values of the HL-LHC, including a 1.5 safety factor. A complete electrical characterization of the key sensor parameters before and after irradiation is presented, studying the leakage current, bulk capacitance, single-strip and inter-strip characteristics. The results confirm the fulfilment of the ATLAS specifications throughout the whole experiment. The study of a wide range of fluences and doses also allows to obtain detailed results, such as the frequency dependence of the bulk capacitance measurements for highly irradiated sensors, or the evolution of the punch-through protection and inter-strip resistance with radiation.

The electronics of the CMS Drift Tubes (DT) chambers will be replaced to operate during High Luminosity (HL-LHC). In the upgraded architecture, optical links (lpGBT, VTRX+) send all signals to the backend, where complex logic running on FPGAs will process the data within trigger latency with precision enough to profit from the full chamber resolution, which in the present system is only possible offline. One of the sixty sectors of the detector was instrumented with the final version of the front-end boards (OBDTs, in two types) during the Winter stop 2022–23. After commissioning and integrating this setup in CMS operations during 2023, its stability has been tested in 2024 LHC collisions. Performance during 2024 campaign is summarized.

For the high-luminosity upgrade of the ATLAS Inner Tracking detector, a new pixel detector will be installed to increase bandwidth and to cope with higher radiation, among other challenges. In this contribution, the design aspects and qualification of the data transmission from pixel modules to optical readout are presented. A focus is put on the data cable bundles and their performance for one of the Pixel sub-systems, the Outer Barrel. The development of a custom system for production testing of the bundles is discussed. Finally, in preparation of the detector integration, developments regarding functionality and connectivity testing are analyzed.

The design and measurement results of a prototype Time-to-Digital Converter (TDC) fabricated in 130 nm CMOS technology are presented. The TDC architecture with analog interpolators was chosen, which was motivated by previous experience in Analog-to-Digital Converter (ADC) design [1]. The measured time difference between the event and the trigger signal is converted to the amplitude and then digitised by a 10-bit ADC. The TDC prototype is functional and achieved good Differential Non-Linearity (DNL) and jitter (below 1 LSB), slightly dependent of the selected time precision. The obtained Integral Non-Linearity (INL) is significantly higher than simulated and should be still improved. The prototype Application-Specific Integrated Circuit (ASIC) has configurable time resolution from 15 ps to 140 ps, which gives the total possible time measure range from ±9.5 ns to ±70 ns. In this paper the architecture of the developed TDC is described, comprising the implementation of the Time-to-Analog Converter (TAC) and 10-bit ADC. The measurements of the prototype 8 channel TDC ASIC, showing its linearity and timing resolution are also shown.

This work describes a custom electronics card named PicoTDC board developed at INFN Bologna, whose goal is to provide fast timing measurements to generic detectors. The board is able to connect to different front-end electronics using a common FMC (FPGA Mezzanine Connector) interface. The fast timing measurements are provided by 2 PicoTDC ASICs from CERN, which supply 128 channels with 3.05 ps LSB. Design choices and performance of the card are discussed. We are also designing a family of front-end cards compatible with the PicoTDC board to improve the flexibility of the board itself and ease the connection to generic detectors and their front end electronics. We then measured the timing resolution achievable with this board, which is compatible with the PicoTDC expected performances.

For the upcoming high-luminosity LHC, the endcap calorimeters of the CMS experiment will be replaced by the high granularity calorimeter (HGCAL), a sampling calorimeter using both silicon and scintillator as active materials in different regions depending on the radiation dose. This contribution describes the integration details of the scintillator-based front-end into the readout chain of HGCAL. A prototype of the SiPM-on-tile readout chain was successfully operated in two recent beam tests at CERN SPS, demonstrating stable operation in a 3 T magnetic field and synchronization of sensor modules across different optical links. For the first time, both the silicon and SiPM-on-tile sensors of HGCAL are integrated into a single system utilizing a Serenity-Z FPGA card. Coarse event data which would be used for trigger logic are read out synchronously for both sensor types and across multiple layers.

The High-Luminosity LHC will start operations for physics in 2029 and aims to record 3000 fb^-1 of proton collision data. This expansion of the dataset will be achieved by a four-fold increase in the number of collisions per bunch crossing, leading to ∼ 10× higher radiation doses and busier events. To cope with those harsher conditions and to be compatible with the new ATLAS data acquisition paradigm, the ATLAS Liquid Argon Calorimeter on-detector electronics will have to be replaced. The presentation will cover the validation of the performance of the new boards, a critical step before launching the full production of about 1500 boards and their installation which is planned to start in 2027.

Particle tracking and imaging detectors are becoming increasingly complex, driven by demands for densely integrated functionality and maximal sensitive area. These challenging requirements can be met using 3D interconnect techniques widely used in industry. In this paper, we present the results of an evaluation of the 3D Through-Silicon-Via (TSV) technology, using the Timepix4 integrated circuit as a test-vehicle. We will present the concepts for 3D integration and test results from TSV-processed chips bonded to custom-designed circuit boards conceived as proofs-of-principle for future detector modules.

The COLUTA (COLumbia-University of Texas at Austin) ASIC is an 8-channel, 15-bit, 40 million samples per second (MSPS), analog-to-digital (ADC) converter designed for the high-luminosity LHC (HL-LHC) upgrade of the Liquid Argon (LAr) calorimeter readout electronics. The production version of the ADC meets and exceeds the specifications for the analog performance and the HL-LHC radiation tolerance. Radiation tolerance test procedure and the results of the irradiation test on pre-production lot chips will be discussed. The production testing will be performed by a custom-designed robotic test setup which will test 80,000 chips required for the upgrade. The chip performance results, and the chip quality information are stored in a local and centralized database. Results from robotic chip-testing of the production lots will be described, along with the yields of the chips which meet the specifications for the upgrade.

Within the context of the ALICE ITS3 collaboration, a set of MAPS small-scale test structures were developed using the 65 nm TPSCo CMOS imaging process with the upgrade of the ALICE inner tracking system as its primary focus. One such sensor, the Circuit Exploratoire 65 nm (CE-65), and its evolution the CE-65v2, were developed to explore charge collection properties for varying configurations including collection layer process (standard, blanket, modified with gap), pixel pitch (15, 18, 22.5 µm), and pixel geometry (square vs hexagonal/staggered). In this work the characterisation of the CE-65v2 chip, based on ⁵⁵Fe lab measurements and test beams at CERN SPS, is presented. Matrix gain uniformity up to the (5%) level was demonstrated for all considered chip configurations. The CE-65v2 chip achieves a spatial resolution of under 2 µm during beam tests. Process modifications allowing for faster charge collection and less charge sharing result in decreased spatial resolution, but a considerably wider range of operation, with both the 15 µm and 22.5 µm chips achieving over 99% efficiency up to a ∼ 180 e^- seed threshold. The results serve to validate the 65 nm TPSCo CMOS process, as well as to motivate design choices in future particle detection experiments.

The Embedded Monitoring and Control Interface (EMCI) and Embedded Monitoring Processor (EMP) system is a state-of-the-art solution developed for the Detector Control System (DCS) upgrade in the ATLAS experiment. The EMCI serves as a radiation-tolerant interface for control and monitoring data of the detector Front-End electronics. The EMP, a multi-processing System on Chip (MPSoC) platform, serves as the interface between the EMCIs and the Back-End of the DCS, providing centralized data handling and monitoring capabilities. The firmware and software ecosystem includes the EMP operating system (epos), dedicated firmware IP blocks, associated software libraries, and OPC UA based middleware applications. This paper focuses on the ongoing hardware verification and development of the firmware and software infrastructure for the EMCI-EMP system.

Cadmium Telluride and Cadmium Zinc Telluride detectors are used in various environments in high-energy, nuclear, medical and astrophysics. They are high-Z materials and have high interaction probability with high energy X-rays and gamma rays. However, the crystal properties, especially various defects have impact on the charge collection efficiency. In this paper we studied the response of the crystallographic defects to estimate their impact on detector performance.

The High-Intensity Heavy-ion Accelerator Facility (HIAF) is a leading platform for heavy-ion scientific research in China with advanced beam current indicators. In these experiments, Low-Gain Avalanche Detectors (LGAD) have become the detector of choice, and the readout circuit of LGAD requires time-to-digital converters (TDC) to convert the time measurement results into digital signals. Since a smaller pixel area is conducive to improving positional resolution and spatial resolution, a TDC using calibration modules instead of delay-locked loops (DLLs) is proposed to achieve lower power consumption and area. The proposed TDC is a 3-stage architecture, reaching an extensive dynamic range and a high resolution. In addition, calibration modules are used to measure the relationship between two adjacent stages of resolution. Thus, the resolution of the TDC could be confirmed under the influence of process, voltage, temperture (PVT) variation. Compared with the TDCs using DLLs, the proposed TDC reduces the power consumption and area. The resolution of the proposed TDC is about 5.13 ps, and the dynamic range is 25.2 ns. The integral nonlinearity (INL) and the differential nonlinearity (DNL) are both less than 0.3 least significant bit (LSB). Including two TDCs, which measure the time of arrival (TOA) and the time of threshold (TOT), respectively, the layout area is 931 μm × 447 μm

This work reports on Total Ionizing Dose (TID) assessment on off-the-shelf LVDS links that will be used for the new trigger and readout system of the ATLAS muon barrel spectrometer within the HL-LHC program. We developed an experimental setup that allows to investigate TID effects on the currents drawn by the devices under test and on their signal integrity, including variations in amplitude, rise/fall time, and bit error rate. No significant variations of these quantities has been observed after integrating the ATLAS target dose of 84.6 Gy. In order to investigate high-dose effects, the irradiation has been extended up to 15.4 kGy. No post-annealing effects were observed. These results complement existing literature, proving the robustness of off-the-shelf LVDS links for the ATLAS environment.

The High-Luminosity Large Hadron Collider (HL-LHC) has motivated a generalized upgrade in electronic systems across all experiments. In the new electronics architecture for the CMS (Compact Muon Solenoid) Drift Tubes detector, the trigger generation moves from on-detector ASICs to the back-end, to be carried out by top-range FPGAs. The new algorithm aims to deliver full-resolution, offline-grade performance in the reconstruction of muon segments. To achieve this objective, meeting the latency and data rate requirements, a high-speed, highly-pipelined FPGA design with several optimizations has been developed. This work describes the architecture and performance of this algorithm, as well as the challenges encountered during implementation and the solutions adopted.

Part of the muon upgrade of the CMS Experiment for the High-Luminosity Large Hadron Collider consists of three new GEM stations, GE1/1, GE2/1 and ME0. The purpose of these stations is to increase the redundancy of the CMS muon spectrometer in the forward endcap regions and to extend the acceptance of the detector up to a pseudorapidity |η| ∼ 2.8 with the ME0 station. To achieve this result, these detectors must be able to withstand the background radiation of the installation environment, with a rate capability of up to 150 kHz/cm². The first station, GE1/1, was installed during the Long Shutdown 2. Since the start of Run 3 in 2022, GE1/1 has been active in CMS operations and data acquisition; this will be the focus of this work. The presence of high radiation in the area where the detector operates is a challenge for the High-Voltage system, since a large charge has to be handled without reducing the effective gain of the detector. This phenomenon leads to a drop in the effective voltage applied and therefore voltage compensation must be applied to have a stable gain. We quantify this effect by measuring the currents flowing in the High-Voltage system of GE1/1 detectors and comparing them with the observed particle hit-rate measured in the same chambers, as a function of LHC beam luminosity. This study, based on data provided by detectors already installed in CMS, aims to test the performance of detectors in terms of rate capability in order to help the development of the GE1/1 station and to support the development and to highlight the operational needs of the next two stations to be built, GE2/1 and ME0.

The design and qualification results of a System on Chip (SoC) Application-Specific Integrated Circuit (ASIC), called FLAXE, fabricated in 130 nm CMOS technology are presented. FLAXE is a readout ASIC designed for ECAL-p, a compact electromagnetic calorimeter being a part of a detector system for Laser Und XFEL Experiment (LUXE) proposed at DESY, Hamburg, as an extension to the European X-ray Free Electron Laser (XFEL) facility. ECAL-p is a sampling calorimeter with a very compact design targeting small Molière radius, comprising 16 (up to 20) layers composed of 3.5 mm (1 X₀) thick tungsten absorber plates interspersed with silicon sensors. Sensor signal is read and shaped by the analogue readout channel, comprising a Charge Sensitive Amplifier (CSA) and a fully differential CR-RC shaper with 50 ns peaking time, which output is digitized in each channel by a 10-bit Successive Approximation Register (SAR) Analog-to-Digital Converter (ADC). Data from ADC are collected into the ASIC internal memory and read out by the Data Acquisition (DAQ) system between Bunch Crossings (BXs). Around 1000 ASICs have been fabricated and a first batch of 142 ASICs has been packaged and tested. The results of the qualification procedure, as well as measurement result of a single ASIC are presented and discussed.

Most of the tracking detectors for high energy particle experiments are filled with silicon detectors since they are radiation hard, they can give very small spatial resolution and they can take advantage of the silicon electronics foundries' developments and production lines. Strip detectors are very useful to cover large areas for tracking purposes, while consuming less power per area compared to pixel sensors. The majority of particle physics experiments use conventional silicon strip detectors fabricated in foundries that do not use stitching, relying on a very small number of foundries worldwide that can provide large amounts of strip detectors. Fabricating strip detectors in a CMOS foundry opens the possibility to use more foundries and to include active elements in the strips for future productions. For the passive CMOS strip detectors project we fabricated strip detectors in a CMOS foundry using two 1 cm² reticles that are stitched together along the wafer. The fabricated strips stitched the reticles three and five times, and it was shown that the performance of those strips is not affected by the stitching. This paper shows 3D TCAD simulations of the stitching area to investigate the possible effects stitching can have on the performance of the strip detectors, considering different stitching mismatches. We will show that the mismatch of stitched structures up to 1 µm does not impact the performance with TCAD simulations which agrees with the results obtained from the measurements.

Semiconductor hybrid pixel detectors with Timepix 3 chips developed by Medipix collaboration at CERN can simultaneously measure deposited energy and time of arrival of individual particle hits in all 256 × 256 pixels with 55 μm pitch size. Leveraging the single-particle detection sensitivity of these chips, there is a potential to develop algorithms for classifying detected single particles into distinct categories corresponding to different particle types. In this study, various machine learning models are introduced, such as recurrent and feedforward neural networks or gradient boosted decision trees, designed to facilitate the classification of single particle events into distinct classes associated to electrons & photons, alpha particles, heavy nuclei (except alpha particles), low energy protons (E ≲ 100 MeV) and high energy protons (E ≳ 100 MeV). All models achieve outcomes with the true positive rate nearing 100% across all classes. The Gaussian Mixture unsupervised machine learning technique is used to differentiate between electron and photon radiation components. The model effectively distinguished between high-energy electrons and low-energy photons, achieving performance comparable to conventionally used heuristic decision trees. All models are trained and tested on an extensive database of experimental data obtained from controlled radiation source experiments.

The High Luminosity LHC (HL-LHC) upgrade mandates a comprehensive overhaul of the CMS Drift Tubes (DT) electronics due to trigger rates surpassing current capabilities. Accordingly, a new DT electronics has been designed that not only overcomes the readout limitations but also, will allow to improve the performance of the muon barrel trigger system by increasing the resolution and reducing the fake rates. The on-detector part of this new electronics will continue to perform the time digitization of the DT chamber signals with the required 0.78 ns but will achieve factors closer to 10 in terms of integration, reducing the power dissipation by half. The core of this new on-detector electronics is the On-detector Board for DT (OBDT) board that will allow integrating up to 240 time digitization channels and forward them without data losses, with ∼10 W of power consumption and operating under radiation environment. The backend system will be based in Advanced Telecommunications Computing Architecture (ATCA) boards and for the first time we have successfully implemented the DT trigger primitive algorithm capable of using the OBDT streamline data and performing the DT muon track reconstruction in the available latency and with very similar to offline resolution. The deployment of OBDTs in a sector of the CMS has allowed to obtain the first results that validate the new architecture and its performance. Rigorous testing procedures have been conducted to ensure the suitability of these systems for the demanding operating conditions of the HL-LHC, with a primary emphasis on functionality and reliability. This report outlines an innovative approach to DT electronics, promising enhanced performance in a challenging HL-LHC environment.

The ALICE Experiment at the Large Hadron Collider (LHC) underwent a major upgrade during the Long Shutdown 2. Several subsystems have been improved, including the ALICE Inner Tracking System (ITS), which has been entirely replaced. The new pixel-only tracker (ITS2) consists of 7 layers of Monolithic Active Pixel Sensors (MAPS) featuring a pixel size of 27×29 μm², with an intrinsic spatial resolution of 5 μm. With 24120 sensors and 12.5 billion pixels, this detector covers an active area of about 10 m² and represents the largest application of the MAPS technology in a high-energy physics experiment to date. The most significant improvements introduced by the ITS2 to the ALICE experiment include a reduction in the impact parameter resolution to approximately 30 μm in both the rφ and z coordinates at a transverse momentum of 1 GeV/c. This is a factor of 3 improvement over the previous detector. Additionally, the standard ITS readout rate has been increased from 1 kHz to 67 kHz in Pb-Pb collisions and to 202 kHz in proton-proton collisions. To ensure stable operations and maintain high data quality a regular calibration is performed, which consists in establishing the charge threshold and the noisy channels of the detector. The ITS2 has been successfully commissioned for LHC Run3, and already operated during proton-proton and Pb-Pb collisions at LHC with excellent performance. This contribution gives an overview of the operational procedures required to maintain an optimal data quality, along with results obtained from calibration and the performance achieved during the LHC Run 3.

Calorimetry at the High-Luminosity LHC (HL-LHC) faces many challenges, particularly in the forward direction, such as radiation tolerance and large in-time event pileup. To meet these challenges, the CMS Collaboration is preparing to replace its current endcap calorimeters for the HL-LHC era with a High-Granularity Calorimeter (HGCAL), featuring an unprecedented transverse and longitudinal segmentation, for both the electromagnetic and hadronic sectors, with 5D information (space-time-energy) read out. The proposed design uses silicon sensors for the electromagnetic section and high-irradiation regions of the hadronic section, while in the low-irradiation regions of the hadronic section plastic scintillator tiles equipped with on-tile silicon photomultipliers (SiPMs) are used. The full HGCAL will have approximately 6 million silicon sensor channels and about 240 thousand channels of scintillator tiles. This will facilitate particle-flow-type calorimetry, where the fine structure of showers can be measured and used to enhance particle identification, energy resolution and pileup rejection.

PERCIVAL is a novel soft X-ray detection system designed for the needs of modern microscopy. By integrating it into the TwinMic end-station at Elettra Sincrotrone Trieste, we conducted an exploratory computational microscopy experiment on biological samples, aiming at evaluating the entire system in a real use-case scenario. We present the methodology to convert the RAW data and our high-resolution image reconstructions.

MAPS (Monolithic Active Pixel Sensors) are emerging as the leading technology for inner tracking detectors in future particle physics and nuclear physics experiments. At CCNU (Central China Normal University), the MIC series MAPS ASICs are currently under development. To facilitate the evaluation of these chips and the readout of telescopes with multiple modules, a flexible chip readout and data acquisition system is being developed. This system comprises a front-end kit and a back-end PCIe-based system called PiDAQ. The PiDAQ card, PDQ142, is built with the AMD Versal Prime series FPGA VM1402. Key features of this board include: PCIe Gen4×8 bus supports throughput up to 14.76 GB/s; on-board memory modules support data buffering with an average throughput exceeding 37.7 GB/s. Furthermore, the board is designed to interface with up to eight front-end modules in speed up to 28 Gb/s per lane, making it ideal for future telescope applications. This paper details the design, hardware, firmware, and preliminary validation of the PDQ142 system.

The Cleopatra ASIC is a 12-channel prototype ASIC for the readout of hydrogenated amorphous silicon sensors used for real-time dosimetry in radiation diagnostic and radiation therapy. The architecture is based on a current to frequency conversion based on the recycling integrator principle in order to cover a dynamic range of four orders of magnitude with high linearity. Three different input amplifier configurations have been implemented in order to check the trade-off between detector capacitance and maximum output frequency. Cleopatra has been designed in CMOS 28 nm technology and succesfully tested in laboratory.

Balloon-borne Instrument for Spectral Scanning of high-altitude Environments (BISSE) is a lightweight gamma-ray measurement setup that can be placed in standard weather balloons and can be retrieved after the flight. This allows multiple flights with a relatively small cost. The purpose of BISSE is to record spectral information on radiation at high altitudes. To obtain good spectral resolution with relatively small weight we use a cadmium zinc telluride (CZT) detector which has crystal dimension of 1 cm cubed. The commercially available detector is housed in a container which holds it at normal pressure at high altitudes. In this paper we present the design of our setup and show some measurement results. We also simulated the expected response of the detector at various altitudes.

Locating radioactive hot spots presents a significant challenge for the nuclear industry and security applications, such as waste management, decommissioning, radiation protection, and the management of nuclear accidents. The detection of fast-neutron emissions offers an alternative technique to gamma imaging for verifying the location of radioactive materials, particularly in cases where gamma imagers face challenges in detection. In this study, we present the performance of a prototype gamma-neutron imaging system based on a custom-fabricated plastic scintillator, designed to effectively discriminate between signals from gamma radiation, fast neutrons, and thermal neutrons. We conducted Geant4 simulations to investigate neutron interactions within the plastic scintillator and compared the simulation results with experimental data. Additionally, we performed experiments on the prototype using a proton beam at the CYRCé facility at IPHC, utilizing a CMOS Monolithic Active Pixel Sensor (MAPS) called MIMOSIS to analyze the beam profile. Through these efforts, we examined neutron interactions with our scintillator, validated the prototype's imaging capabilities under proton beam exposure, and conducted a calibration study of its energy response.

The CMS Electromagnetic Calorimeter (ECAL) is a homogeneous PbWO₄-based detector. The upcoming High-Luminosity upgrade of the CERN LHC will provide detectors with unprecedented instantaneous luminosity, entailing an increase of the average number of proton-proton collisions per bunch crossing up to a value of 200. To cope with such busy environment and with the trigger latency and rate, the ECAL readout and trigger electronics system will be replaced. The front-end electronics will deploy custom ASICs optimised for precise timing, improved signal discrimination, lossless data compression, and fast transmission. Off-detector FPGA processor boards will form trigger primitives and perform basic signal reconstruction. The upgraded system has been validated over several test beam campaigns. In terms of physics performance, it will match the outstanding energy resolution of the current ECAL detector, while significantly enhancing the time resolution of electrons and photons above 50 GeV.

With the completion and operation of a series of high-performance neutron sources, such as the China Spallation Neutron Source (CSNS), various neutron scattering spectrometers have continuously increased their performance requirements. One important aspect is to reduce collisions between scattered neutrons and air molecules during neutron scattering experiments, thereby reducing background noise and obtaining highly accurate experimental measurement results. This paper presents an application-specific integrated circuit (ASIC) dedicated to position-sensitive Helium-3 tubes neutron detector, which introduces peak detection and holder (PDH) circuits on the basis of traditional front-end electronics. Through a specific design, the switches and holding capacitor of the PDH module are isolated, ensuring that the holding voltage is not affected by switch noise, and maximizing the measurement accuracy of the PDH module. The 8 channel ASIC, realized in 0.18 μm CMOS technology, has a 10 fC to 1 pC input signal range with a linearity error within 0.22% to 1%. The PDH module is supplied with a single voltage of 1.8 V with a total power consumption of 350 μW with a layout area of 361 μm × 68 μm. The ASIC further enhances system integration, allowing the analog-to-digital conversion module to employ low-speed ADCs, thereby reducing the overall power consumption of the readout system. This enables the entire detector to operate in a vacuum environment, providing a new electronic readout solution for future neutron scattering and imaging experiments.

Photon-counting hybrid pixel detector chips, such as those based on the Medipix3RX technology, have been central to advancements in spectral and multi-dimensional imaging at synchrotron facilities. As these facilities continue to improve with ongoing upgrades, there is a growing demand for large-area cameras that not only handle increased X-ray flux performances but also integrate effectively into various scientific setups with minimal power consumption. This work focuses on optimizing the energy efficiency of Medipix3RX readout chips used in the context of large-area X-ray photon-counting detectors. We have introduced several power optimization techniques, including dynamic frequency and voltage scaling, and the incorporation of standby/sleep modes into sensor operation. These methods have significantly reduced power consumption, thereby allowing for simplified cooling systems and enhanced durability without compromising the robustness and reliability of the system. Experimental results demonstrate that applying dynamic voltage and frequency scaling can reduce power consumption by 5%, while the clock gating technique can reduce it by up to 23%. Furthermore, the implementation of a sleep mode during periods of inactivity reduces heat dissipation, improving sensor temperature stability, while also reducing overall energy requirements by up to 40% compared to continuous operation. A detailed characterization of the internal parameters of the Medipix3RX analog front-end has enabled us to identify optimal operating points that balance low power consumption with high performance, which is crucial for maintaining low noise levels and fast count rates in challenging experimental environments.

Photon-counting detectors (PCDs) are an attractive technology; they provide multiple- or dual-energy (DE) images after a single X-ray exposure. We evaluated the fundamental imaging performance of a CdTe-based DE PCD embedded with an optional anticoincidence (AC) function that aggregates the signals spread over neighboring pixels and casts this sum to the pixel that represents the highest signal. Furthermore, we compared the performance of this CdTe-based DE PCD with conventional flat-panel detectors (FPDs) using the same X-ray spectrum (70 kV and 21-mm aluminum filtration). The AC option improves the modulation-transfer function of the PCD by suppressing the possible double counting induced by a Cd or Te K-edge characteristic X-ray photon, which causes a count in a pixel in the proximity of the photoelectric event. These characteristic X-ray interactions correlate between low- and high-energy images, resulting in a cross noise-power spectrum (NPS) whose magnitude decreases with increasing spatial frequency. In contrast, the AC option produces an uncorrelated NPS. The detective quantum efficiencies (DQEs) of the DE PCD with AC-off and -on were identical, when the cross-NPS was compensated for, to those for the images obtained by summing low- and high-energy images. Furthermore, the DQE performance of the PCD was not degraded upon lowering the air kerma levels and even dominated that of the FPDs.

The latest generation of Timepix series hybrid pixel detectors enhance particle tracking with high spatial and temporal resolution. However, their high hit-rate capability poses challenges for data processing, particularly in multidetector configurations or systems like Timepix4. Storing and processing each hit offline is inefficient for such high data throughput. To efficiently group partly unsorted pixel hits into clusters for particle event characterization, we explore parallel approaches for online clustering to enable real-time data reduction. Although using multiple CPU cores improved throughput, scaling linearly with the number of cores, load-balancing issues between processing and I/O led to occasional data loss. We propose a parallel connected component labeling algorithm using a union-find structure with path compression optimized for zero-suppression data encoding. Our GPU implementation achieved a throughput of up to 300 million hits per second, providing a two-order-of-magnitude speedup over compared CPU-based methods while also freeing CPU resources for I/O handling and reducing the data loss.

The FASER experiment at the LHC aims to detect new, long-lived fundamental particles. A tungsten-silicon (W-Si) preshower detector is being developed to enhance the experiment's ability to distinguish between closely spaced photon pairs with energies on the order of TeV and separations as small as 200 µm. This detector will use a monolithic silicon pixel sensor fabricated with 130 nm SiGe BiCMOS technology. Initial tests were conducted on the production ASIC, after evaluating the performance of the preproduction ASIC. The first tests on the production ASIC indicate that the essential components of the monolithic silicon pixel detector are operating as expected. Two calibration methods were developed to reconstruct the charge of the FASER preshower detector, from the ASICs' ADC values.

T2K is a long baseline neutrino experiment, entering Phase II with a Near Detector upgrade. The T2K near detector (ND280) upgrade consists of the installation of three new detector systems: a plastic scintillator neutrino active target (Super-FGD), two time projection chambers (HA-TPC) and a time of flight detector (TOF). The Super-FGD is composed of 2-million 1 cm³ scintillating cubes read by almost 60 thousand wavelength-shifting (WLS) fibers coupled to an MPPC on one end. Given the large number of channels, the limited space inside magnetic environment, and the limited time from production to installation, the development and testing of the Front-end electronics boards (FEB) for the read-out of the Super-FGD channels represented a challenging task for the success of the upgrade. This work presents the performance tests confirming that the FEB aligns with detector requirements, and the hardware qualification of 240 FEBs through a custom QC test bench designed to detect and locate hardware failures to speed up the repairing process. Installation of the electronics in the detector took place in March 2024, one year after the beginning of the FEB mass production, and the first successful neutrino beam run took place in June of the same year.

For the High-Luminosity Large Hadron Collider, the ATLAS experiment will replace its current Inner Detector with an all-silicon Inner Tracker (ITk), consisting of pixel and strip systems. In the end-cap, silicon sensor modules of the strip system are mounted onto support structures called "petals". To facilitate the assembly of petals, an automated system has been developed which streamlines the production process and ensures uniformity. This paper presents the latest results from the assembly of the first ITk pre-production petals, including characterization of their electrical performance and studies of their robustness at temperatures ≤ -35 ^∘C.

The high luminosity operation of the LHC will deliver collisions with a luminosity about 10 times the original design value. This poses a big challenge for trigger and data acquisition due to nearly 200 overlapping collisions, called pile up, within the same bunch crossing. Disentanglement of the pileup particles from those of interesting physics processes is achieved by implementing the Pile-Up Per Particle Identification (PUPPI) algorithm. We present the strategy for implementation of PUPPI at the Level-1 (L1) trigger, focusing on the Hadron Forward (HF) Calorimeter detector of the CMS experiment. The main features of the custom firmware developed for this purpose is discussed.

Coded Aperture γ-cameras have been extensively used in applications ranging from astrophysics to nuclear medicine for imaging radioactive source distributions. These devices allow the identification of the direction of γ-emitters by analyzing the shadow patterns projected onto pixelated detectors. In this work, we propose a novel approach based on Convolutional Neural Networks (CNNs) for accurately localizing radioactive sources in 3D using one coded aperture gamma camera. The CNN is trained using simulated shadowgrams generated by a custom simulation tool, with sources placed at various positions within the near-field, ranging from 20 cm to 120 cm from the detector. Unlike previous methods that focused on estimating angular coordinates, our model also accurately estimates the distance of the source, achieving a distance estimation accuracy of 10 mm, in addition to determining the polar and azimuthal angles. This capability is particularly relevant for medical imaging applications, where precise localization of radioactive sources is crucial. The results of our study demonstrate the potential of CNN-based algorithms in improving the accuracy and reliability of single-detector systems in near-field radioactive source localization.

This paper reviews the bus tapes used for the barrel and end cap detectors for the ATLAS ITk strip detector. The long copper/polyimide tapes with narrow track and gap are very challenging to produce with an acceptable yield. Two different technologies for these tapes are compared. After several iterations, barrel and end cap tapes are in production at two different manufacturers. Results from the electrical and dimensional QC show that both approaches meet the tight specifications. Tests of the radiation tolerance are also discussed.

A demonstrator for each slice of the ATLAS pixel detector was built to replicate the real detector and provide early solutions for operating and maintaining its components. This system-level testing of the all-silicon Inner Tracker (ITk) pixel detector for the ATLAS experiment at CERN's HL-LHC encompasses a wide array of system components, which is essential for managing the increased luminosity and radiation levels expected at HL-LHC, thereby enhancing tracking performance. Utilizing advanced silicon sensor technologies, serial powering, and lightweight carbon fiber structures, the demonstrator and assembled components on the support structure will undergo several studies for verification and commissioning. Extensive tests on serial powering, monitoring, and data acquisition were conducted, ensuring the system's robustness and reliability for future high-energy physics experiments. Additionally, three different sub-components will be introduced for the novel ITk pixel detector, specifically designed for the outer barrel (OB), outer end caps (OEC), and inner system (IS) sections.

The double hollow cathode metal ion source produces metal elements by hollow cathode sputtering and has a high material utilization rate. However, at present, a high magnetic mirror field is generated by an electromagnet, which is huge in volume and the edge field of a high magnetic mirror field seriously affects ion extraction. Miniaturization of the discharge chamber is a feasible method to solve this problem. In this paper, a two-dimensional fluid model of the double hollow cathode discharge structure under magnetic mirror field constraints is developed to study the double hollow cathode discharge and ion sputtering. The results show that the sputtering depth flux is formed above the sputtering voltage of 400 V. The evolution of the sputtering depth profile results from the combined effect of the wall ion flux, spatial radial electric field, and ion collisions. The location of the maximum ion sputtering depth depends mainly on the energetic ions entering the hollow cathode from the anode. The magnetic field and thermal electron emission strongly correlate with the sputtering depth. A small discharge chamber structure is proposed with a hollow cathode length of 36 mm, which is 24 mm smaller than the ion source established by Peking University in 2017, using a magnetic mirror field of 1400 Gs at the center point, which can be realized in the form of a permanent magnet. The electron density in the center of the discharge chamber is 2.88 × 10²¹ m^-3 and 99% of the electrons are confined within a radius of about 3.7 mm.

Mineral-Insulated Metal-Sheathed thermocouples exhibit extended lifespan and resilience in harsh environments, owing to their protective sheath. However, these thermocouples are prone to failure in a highly acidic medium such as nuclear fuel reprocessing plants. This paper investigates the degradation phenomena and its effect on measurement accuracy when a thermocouple with damage to its protective sheath is immersed in a corrosive medium. The objective is to assess the thermocouple's reliability by micro machining a small hole to simulate sheath damage, facilitating direct contact between the corrosive medium and the sensing materials of a K-type thermocouple. The thermocouples with sheath defects were subjected to aging in different concentrations of acidic medium at a constant temperature, leading to eventual failure. The time-to-failure data of thermocouples at each concentration is analyzed using the Weibull distribution. This study establishes a thermocouple accelerated life-stress relationship using the Inverse Power Law under a ruptured sheath condition. The study also explores the correlation between the residual life and the position of simulated ruptures. ANOVA is employed to test the hypotheses regarding the influence of rupture position on thermocouple performance. It is shown that the location of damage is statistically significant in determining the thermocouple's residual life under damaged sheath condition.

Two types of single sphere neutron spectrometers based on a set of micro-structured semiconductor neutron detectors (MSNDs) were designed. Each neutron spectrometer consists of 31 MSNDs symmetrically located at certain positions along three perpendicular axes within a single moderating sphere. One uses high-density polyethylene (HDPE) moderating sphere, while the other uses borated polyethylene rather than HDPE as the outermost thin shell of moderating sphere. The second design aims to eliminate the backscattering effects in order to improve the response isotropy of slow neutrons. For two neutron spectrometers, a charged particle tracking (CPT) model was built with Monte Carlo transport code MCNPX to calculate neutron responses for 53 mono-energies from 10^-9 MeV to 20 MeV for three different irradiation geometries. The feasibility of two neutron spectrometers and the isotropy of neutron responses were evaluated by simulating a set of irradiation exposures to different typical neutron spectra. A generalized regression neural network (GRNN) method was used to unfold neutron spectra without the need to input preset spectral information by the users. The neutron spectrum unfolding performance was assessed quantitatively by index Q_s and the results from two spectrometers were compared and analyzed.

The study of coke reactivity under high temperature conditions is crucial for understanding its behavior in industrial processes. This study presents a novel compact heating furnace, developed for in-situ synchrotron small-angle X-ray scattering (SAXS) studies on the high-temperature reactivity of coke. The furnace achieves temperatures up to 1400^∘C at a heating rate of 12^∘C/min and enables steam introduction, simulating industrial conditions. Combination of the furnace with the in-situ SAXS setup at synchrotron radiation facilities facilitates real-time monitoring of structural changes at nanoscale in coke under various temperature and atmospheric conditions. This advancement offers a robust experimental platform for studying coke reactivity, with potential benefits for optimizing industrial processes and reducing environmental impact.

The timing skew mismatch is one of the limitations in the Time-interleaved Analog-to-Digital Converter (TIADC) system seriously degrades the system performance. In order to solve this problem, this paper proposes an algorithm to detect the timing skew mismatch. The self-adaptive Particle Swarm Optimization (SAPSO) algorithm was used to detect the timing skew mismatch in the TIADC system, and the variable delay line (VDL) was used to calibrate the detected timing skew mismatch. For verifying the effectiveness of the proposed algorithm, a 4-channel, 1 GHz and 18 bits TIADC system model with timing skew mismatch is established. The simulation results show that the proposed algorithm significantly improves the performance of the TIADC system, which the Spurious Free Dynamic Range (SFDR) is increased by 61.1 dB on average, the Signal-to-Noise Ratio (SNR) is increased by 59.17 dB on average, and the effective Number of Bits (ENOB) is increased by 9.83 bits on average. Compared with the previous calibration algorithms, the proposed method has the advantages of simple structure, fast detection speed and high accuracy.

To deeply understand the development status and research hotspots of high voltage pulsed electric field (HVPEF) technology, this paper takes the Web of Science (WOS) core collection Science Citation Index Expanded (SCI-EXPANDED) database as the literature source, and sets `high voltage pulsed electric field' as the keyword search. The collected 3041 articles (January 1, 1990–December 31, 2022) were used as the research object. CiteSpace and VOSviewer software were used to visually analyze the number of publications, citations, authors, institutions, journals, countries, disciplines, and keywords, and draw a visual map to explore the development context and content evolution of the technology on a global scale. It is found that the HVPEF technology is in a stage of rapid development, and the number of published papers and citations of relevant literature is on the rise. This field has been centered on China and the United States, forming a closely cooperative academic research network. There is also a close cooperative relationship between different authors and institutions. In addition, the research on HVPEF is mainly applied to physics, plasma, etc., but food, materials, and other disciplines are also involved. The research content extends from the PEF itself to cells, microorganisms, etc., and gradually from principle-based research to the use of technology to achieve the purpose. In recent years, the research on the extraction of active compounds assisted by PEF is increasing, which is likely to become one of the future research hotspots in this field. In summary, the HVPEF is receiving more and more attention, and has a very good research and application prospect.

Metastability exchange optical pumping (MEOP) is a widely used technique for producing polarized ³He. In connection with an experiment to search for the electric dipole moment of the neutron (nEDM) we have built a MEOP based ³He polarization and injection system to prepare 80 % polarized ³He at room temperature which will be injected into a ∼ 400 mK measurement cell filled with superfluid ⁴He. We describe the polarization and injection system, which is designed to allow for final concentrations of 10^-8–10^-10 of 80% polarized ³He in the superfluid filled measurement cell. Only ≈ 0.72% polarization loss due to gradients is expected during injection

A numerical model based on hydrodynamic approach has been developed to emulate the device dynamics of active target Time Projection Chamber which is utilized for studying nuclear reaction through three-dimensional tracking of concerned low-energy particles. The proposed model has been used to investigate the performance of a prototype active target Time Projection Chamber, namely SAT-TPC, to be fabricated at Saha Institute of Nuclear Physics, for its application in nuclear physics experiments. A case study of non-relativistic elastic scattering ⁴He + ¹²C with beam energy 25 MeV and current 2.3 pA has been opted for this purpose. The effect of beam induced space charge on the tracking performance the SAT-TPC prototype has been studied to optimize the beam current and scheme of the anode readout segmentation. The model has been validated by comparing its results to that of a particle model used to explain observed distortion in scattered particle tracks in a low-energy nuclear physics experiment.

The accelerator-based boron neutron capture therapy (AB-BNCT) facility is being developed worldwide due to its advantages, including easy maintenance, low construction costs, and high safety. To minimize both the length and cost of the accelerator, we propose a combined acceleration structure that utilizes a radiofrequency quadrupole linac (RFQ) in conjunction with a crossbar H-mode drift tube linac (CH-DTL). The CH-DTL rapidly accelerates the beam to the required energy after the RFQ, with output energy adjustable from 2.2 MeV to 3.2 MeV. We have completed the RF electromagnetic design and optimization of the CH-DTL cavity to fulfill beam dynamics requirements while achieving high effective shunt impedance. Additionally, we designed the cooling channels and conducted multi-physics analyses to evaluate the cavity's performance during continuous wave operation.

The coupling correction system of the future SKIF light source has been optimized with the use of numerical simulation. It includes 128 BPMs (out of 224), 128 skew-quadrupoles out of 256 in MBA sections and 32 skew-quadrupoles in dispersion-free intervals. The system is complementary to the global correction and is intended to suppress simultaneously vertical dispersion and linear difference resonance. High efficiency of the EVD-based correction method has been demonstrated at various numerical examples. The possibility of determining the width of the linear difference resonance, which is necessary for such a correction, by the slope of the ellipses of normal modes is under study. The modes are resonantly swung and their elliptical shape is reproduced according to the TbT (turn-by-turn) data of the BPMs. The results of the corresponding real experiment on VEPP-4M are presented, as well as the numerical experiment on the swing of eigenmodes on the SKIF.

Compact high-gradient quadrupole magnets are required on both sides of the interaction points (IP) in the Circular Electron Positron Collider (CEPC) interaction region (IR). The dual-aperture superconducting quadrupole magnet Q1a is positioned closest to the IP with a crossing angle of 33 mrad between the two apertures. The electromagnetic design and development of Q1a faces great challenges due to the difficulties associated with the small aperture, high gradient and the magnetic field interference. This paper presents the electromagnetic design scheme of CEPC IR quadrupole magnets and the development of a high gradient superconducting quadrupole experimental magnet. Firstly, by comparing the electromagnetic properties and technological characteristics of three commonly used quadrupole superconducting coils, the design scheme of the superconducting quadrupole magnet for the CEPC final focusing system is determined. Then, the electromagnetic design and optimization of a cos 2θ experimental magnet is presented, the manufacturing process of the experimental magnet is introduced. Finally, the cryogenic excitation test of the experimental magnet is described and the physical design scheme of the high-gradient superconducting magnet for final focusing system in CEPC IR is verified.

The aim of the presented work is the development of single-stage amplification resistive Micro Pattern Gas Detectors (MPGD) based on Micromegas technology with the following characteristics: ability to efficiently operate up to 10 MHz/cm² counting rate; scalability to large areas; fine granularity readout with small pads of the order of mm²; good spatial and time resolutions (below 100 um and 10 ns, respectively). The miniaturization of the readout elements and the optimization of the spark protection system, as well as the stability and robustness under operation, are the primary challenges of the project. Two families of resistive patterns were realized using different techniques: pad-patterned embedded resistors and double-layer of Diamond Like Carbon (DLC) structures foils. The main difference between them is that for the embedded resistors the charge is evacuated through independent pads, for double-layer DLC the resistive layers are continuous and uniform and the charge is evacuated through a network of dot-connections, several millimetres apart. Using the DLC technique, a medium-size detector with an active area of 400 cm² was recently built and tested, with the main results reported in this paper. Additionally, a large module (40 cm² x 50 cm² active area), suitable for tiling large systems in future experiments, has been successfully realised and is currently undergoing testing and performance studies. The characterization and performance studies of the detectors were conducted using radioactive sources and an X-rays generator, with the detectors operated with various gas mixtures. A comparison of the results obtained with different resistive layouts and configurations is provided, with a particular focus on the response under high-rate exposure. Key results on tracking and timing performance from test-beam data for the latest constructed medium-size detector are also presented.

The HT-6M device has been upgraded and rebranded as the Thailand Tokamak 1 (TT-1), which has been reinstalled and is now operational in Thailand. In tokamak discharge experiments, precise monitoring of plasma position and the implementation of effective feedback control are essential for ensuring the stability of the high-temperature plasma. Accurate calculation of plasma displacement is critical to the success of the experiment. This paper presents a method for calculating plasma displacement through a multi-probe fitting technique, utilizing data from twelve magnetic field probes. Initially, magnetic field signals generated by the plasma are collected via multiple magnetic field probes installed poloidally outside the vacuum chamber, coupled with corresponding signal conditioning and integration circuits, with each probe undergoing calibration. Subsequently, during tokamak discharges, interference signals from the toroidal field coils, ohmic heating coils, and vertical field coils are generated by the magnetic system and corrected through a detailed calibration process. Lastly, the distances between the probes and the plasma are computed using data from the magnetic field probes, which are arranged in a circular configuration. The least squares method is employed to formulate a residual equation for fitting the actual plasma displacement. The effectiveness of this approach was validated through experimental data from the TT-1 device, demonstrating that the calculated plasma displacement exhibits a consistent trend with the CCD video recordings. This multi-probe displacement calculation method enables precise control of plasma displacement, thereby providing theoretical support for tokamak experiments and establishing a foundation for future experimental operations and data analysis.

Neutron measurement systems play a crucial role in many fields. However, testing these systems requires neutron sources, which pose radiation hazards. As a safer alternative, developers often opt for simulated neutron signal generators. The goal of this study is to develop a virtual neutron signal generator that meets the development needs of neutron measurement system in pulse mode, campbell mode, and current mode, providing a non-nuclear auxiliary design tool. Inside the Loongson CPU, three digital channels are used to generate pulse signal, campbell signal and current signal. Each digital channel consists of the amplitude module, trigger module and waveform module. The amplitude module uses either measured spectrum or simulated spectrum generated by GEANT4 to obtain physically meaningful neutron pulse amplitudes. The trigger module generates a high-speed triggered clock sequence based on the exponentially distributed time intervals between adjacent neutron pulses. The waveform module generates the waveform of neutron signals. The neutron signals generated inside the Loongson CPU are transmitted to the FPGA via USB3.0. Then, the FPGA outputs virtual neutron analog signals through DAC. Experimental results show that this virtual neutron signal generator can accurately produce virtual neutron analog signals, making it suitable as a testing tool for neutron measurement systems.

An innovative residual analysis based method is proposed for pulse shape discrimination and segregation of neutron and gamma pulses of liquid scintillator-based detector (BC501A). This study develops a simple and efficient algorithm for discrimination of neutrons and gammas from mixed environment and then segregate the neutron and gamma pulses into two label datasets. This method involves analyzing the residuals between the measured pulse and the reference gamma pulse in normalized scale. By examining these residuals, users can identify characteristics unique to each type of radiation. The pulse shape discrimination performance obtained for a 5 inches by 5 inches (length by diameter) liquid scintillator detector using this residual method is found to be 20% better compared to that obtained using traditional charge comparison method.

In the neutron-sensitive Anger camera, the scintillator is directly coupled to the photodetectors, such as multiplier tubes or silicon-photomultipliers (SiPMs), and the incident position of the neutron is determined by the center of gravity of the photon distribution from the scintillating material. The photodetectors in the neutron Anger camera are typically arranged in arrays with multiple pixel outputs. To reduce the number of readout channels, the front-end electronics often employ analog signal multiplexing methods, such as row-column summation and resistor networks. However, these methods increase channel crosstalk and noise after compression. In this paper, we propose reading out each pixel of the multi-anode photomultiplier tube (MaPMT) individually and digitizing each analog channel via waveform capture. This approach allows direct collection of the signal from each analog channel, and we use the pulse amplitude method to achieve neutron-gamma discrimination for GS20 scintillator. We tested the neutron two-dimensional imaging capability of the anger camera system using a Cf-252 slowed neutron beam in the laboratory. The neutron position resolution was estimated using the knife-edge function method with B₄C mask. By combining this with the traditional center-of-gravity method, we achieved a position resolution of 1.2 mm (FWHM).

We propose a system to directly measure H_p(3) quantity both in calibration conditions at laboratories and at arbitrary conditions at irradiation facilities. A commercial ionisation chamber is inserted in a spherical phantom of PMMA such that the system achieves a relatively constant response in terms of H_p(3) and matches the requirements for a secondary standard for H_p(3) quantity. The H_p(3) ionisation chamber was characterized in a dosimetry calibration laboratory under reference conditions and then, as a proof of concept, it was also tested in a work place field at an interventional cardiology department from a hospital. The design method and the measurement results are presented.

Accelerator-based neutron sources are critical infrastructures in today's scientific research and industrial fields, with the neutron source target being the key component determining the performance of the neutron source. Traditional accelerator neutron source targets typically use homogeneous elemental materials with high neutron yield as the target material. These materials face challenges in terms of operational lifespan under high-temperature and high-radiation environments. The design of next-generation high brilliance neutron sources demands target materials with better thermal conductivity, longer irradiation lifespan, and superior corrosion resistance. Tungsten has its high neutron yield, and tungsten alloys exhibit these advantageous properties. This paper employs the Monte Carlo method to calculate neutron yield, radioactivity and radiation damage of two common tungsten alloys, W-TiC and W-ZrC. The results indicate that, with minor doping to improve mechanical properties and manufacturability, the performance of tungsten alloys can also meet the requirements for high-brilliance neutron targets, provide reference for the development of the next generation neutron target.

We present an innovative charge detector with high resolution and wide dynamic range designed to fulfill the requirements of a monitoring system for a high energy ion beam. The detector prototype, constructed using Si photodiodes and a custom readout electronics, underwent extensive testing during HERD and AMS beam tests at CERN SPS facilities. Initial testing showcased the detector's exceptional performance, emphasizing both high resolution and a dynamic range capable of measuring nuclei with atomic numbers ranging from 1 to 80. The prototype's compatibility with fast, quasi real-time data analysis qualifies it as an ideal candidate for online applications. This article presents the results from the testing phase of the prototype, highlighting its capabilities and performance. Ongoing detector development, potential applications, and future developments aimed at enhancing the detector's functionality and versatility are also discussed.

This article describes a radon emanation measurement technique using liquid scintillator counting. A model for radon loading and transport is described, along with its calibration. Detector background and blank have been studied and quantified. The Minimal detectable activity has been determined for the counting setup using a toy Monte Carlo simulation. The measurement technique is validated using a butyl rubber sample previously used for cross-calibration between different radon counting facilities.

This paper introduces a high-performance Soft-Core Processor based data acquisition system designed for handling Resistive Plate Chambers (RPCs). The DAQ consist of FPGA-based hardware equipped with Soft-Core Processor and embedded hardwired Ethernet controllers named RPC-DAQ, offering a versatile and fast network-enabled data acquisition solution. A soft processor, NIOS, is instantiated within an Intel Cyclone IV FPGA, overseeing control, communication, and data transfer with remote processing units. These integrated RPC-DAQ units, in substantial numbers, connect to a limited set of high-end processing units via LAN switches. This paper provides a detailed account of the software implementation scheme for the NIOS processor in the RPC-DAQ system. A remarkable 28,800 RPC-DAQ units will be deployed in proximity to the RPCs, serving the proposed INO-ICAL experiment in Theni-Madurai, Tamil Nadu. The network-enabled RPC-DAQ units controlled by the soft processor offloads FPGA tasks including event data acquisition, periodic health monitoring of RPCs, command interfaces, high voltage control, and data transfer to back-end data concentrators. Communication and data transfer are executed efficiently via TCP and UDP protocols over a 100 Mbps Ethernet interface. This system provides innovative solutions to improve data acquisition and control in large-scale scientific experiments.

The liquid scintillation counting is widely used in α and β nuclides activity measurements of atmospheric, groundwater and biological samples, with the advantages of high detection efficiency, easy sample preparation, reproducibility and low cost. However, single photons caused by mixing of samples and scintillation cocktails affect the accuracy of activity measurements, especially for low energy β-nuclide such as ⁵⁵Fe and ¹⁴C. A novel method to eliminate the single photons based on the analysis of signal time characteristic was developed and a liquid scintillation counter made of a fast time response photomultiplier tube (PMT), a high-speed comparator, and a field programmable gate array (FPGA) based activity measurement system was designed. The FPGA based activity measurement system consisted of pulse width measurement, pulse width discrimination, activity calculation, and display modules. The accurate measurement of pulse width was achieved by digital phase-shifting. The counter was scaled and calibrated with standard ¹⁴C liquid scintillation cocktails. The results show that for ¹⁴C liquid scintillation samples with activities of 72.20 Bq and 732.37 Bq, the relative deviation is less than 1 %.

A compact collinear wakefield accelerator has been designed for an X-ray free-electron laser capable of operating at a pulse repetition rate in the tens of kilohertz. The maximum achievable accelerating gradient has been determined, with its limitation linked to beam breakup instability. The fabrication techniques for the principal components of the accelerator including wakefield generation, couplers for excess power extraction and diagnostics, focusing quadrupoles, and a novel undulator have been discussed. Results from various laboratory and beam-based tests on these components have been compared to their original design specifications and demonstrated very good agreement. A preliminary design for the XFEL has been presented, featuring a novel small-period, force-neutral, adjustable-phase undulator.

Silicon detector technologies are often employed for high energy particle physics applications due to their excellent radiation hardness. Radiation damage in the form of bulk or substrate damage is dependent on the incident particle species and energy. The fluence is therefore often quoted as the 1 MeV neutron equivalent fluence, with hardness factors being the scaling quantity. The hardness factor can be determined by analysing the change in the leakage current of silicon pad diodes post-irradiation. Using the MC40 cyclotron facility at the University of Birmingham, n-in-p FZ silicon pad diodes were irradiated to several fluence points at three different proton beam energies. The hardness factors acquired were 3.07 ± 0.37 for 10.5 MeV protons, 2.73 ± 0.27 for 16.4 MeV protons and 2.19 ± 0.22 for 24.3 MeV protons. The value for 16.4 MeV protons agrees with the theoretical predictions, whereas the values for 10.5 MeV and 24.3 MeV are lower than predicted by the same calculations.

A large number of nuclear power plants are approaching decommissioning, and the low-level radioactive waste discharged during the decommissioning process may increase environmental radioactive background. There have been no reports on the accurate differentiation of alpha, beta and gamma signals from low-level radioactive water and their corresponding activityvalues. We have developed a prototype of a large area phoswich detector with the intention of establishing a detection system for real-time monitoring of gross alpha and gross beta radioactivity levels in water, enabling prompt response in case of elevated radioactivity concentrations. The phoswich detector features two layers of scintillators, and the size of the scintillator and light guide was determined by using Geant4 simulation. The first layer is a 200 mm× 200 mm× 10 mm-plastic scintillator coated with 7 mg/cm² thick ZnS(Ag)that measures alpha and beta particles, the second layer is a 200 mm× 200 mm× 10 mm-plastic scintillator that measures gammarays, which reduces the background interference in the main detector, and the two layers ofscintillator are coupled to a photomultiplier(PMT) through a 6 mm thick light guide. The alpha and beta signals detected were analyzed by usinga digitizer. Due to the significant difference in the decay times of the alpha and beta pulses, pulse shape discrimination (PSD) is very effective. We obtained a 2D PSD scatter plot with a particle discrimination line position of PSD = 0.562 and a figure of merit (FOM) = 1.4134. We measured the alpha and beta detection efficiencies and the background count rate under lead shielding. The detection efficiency when the source is placed at different positions was measured by combining simulation and experiment. We also verified the ability of the prototype to detect alpha/beta particles in low-level radioactive water, which can detect and distinguish alpha and beta particles at different radioactive activity levels in water from 1 Bq/L to 50 Bq/L within 1 hour of counting time. After setting up the water tank and detection system, it can be applied for continuous monitoring of low-level radioactive water around decommissioned nuclear facilities.

A study has been performed to understand the effects of radiation damage on various plastic scintillator tiles considered for a possible upgrade of the hadron calorimeter of the CMS detector. Measurements were made with unirradiated tiles and with tiles that had been irradiated in the CMS collision hall to a dose of 44 kGy. Results are presented for the tiles of different shapes in terms of the energy spectrum, efficiency as a function of the position at which each tile was hit, as well as light yield. All the tiles showed a light reduction of up to about 50%. The tiles with the shape currently used in the CMS detector did not see increased non-uniformity of light collection, while a significant disuniformity was observed for the tiles considered as alternatives.

Carbon fiber reinforced polymers (CFRP) are widely used in fields such as aviation and aerospace. However, subtle defects can significantly impact the material's service life, making defect detection a critical priority. This paper presents a method for detecting delamination defects in carbon fiber reinforced composites (CFRP) using line laser infrared thermography. A preprocessing approach combining differential thermography and frequency-domain filtering is proposed to effectively eliminate the trailing artifacts caused by line laser scanning, resulting in defect feature images with an improved signal-to-noise ratio. Utilizing the preprocessed frequency-domain magnitude image data, an improved Fuzzy C-Means clustering segmentation algorithm is developed, achieving high-precision edge detection of layered defects with an average accuracy of 95.0%. Furthermore, defect depth classification based on the frequency-domain magnitude data is performed using the K-Nearest Neighbor (KNN) algorithm, yielding an average accuracy of 98.8%. These results validate the effectiveness of the proposed algorithms for defect edge detection and depth assessment.

The electrocardiogram (ECG) signal is often contaminated by various noises during acquisition and transmission, and the denoising effect directly affects the diagnosis of heart diseases. To improve the denoising effect, this paper proposes an improved Complete Ensemble Empirical Mode Decomposition (CEEMDAN)-wavelet thresholding and singular spectrum analysis (SSA) joint denoising method. First, the noise-dominated high-frequency intrinsic mode function (IMF) is identified using CEEMDAN; second, it is denoised to reduce high-frequency noise by the improved wavelet thresholding technique; and then, SSA is used to remove baseline wander (BW); finally, to verify the effectiveness of this denoising method, the root mean square error (RMSE) and signal-to-noise ratio (SNR) are used as the evaluation criteria for the denoising effect and the standard MIT-BIH ECG noise database signals are used for verification. The validation results show that compared with the existing ECG denoising methods, the denoising method improves the SNR by 39%∼ 55% and reduces the RMSE by 18%∼ 42%. The method can be used as an effective tool for ECG signal denoising and provide a better basis for diagnosis in computerized automated medical systems.

Following the Phase-II upgrade during Long Shutdown (LS3), the LHC aims to reach a peak instantaneous luminosity of 7.5× 10³⁴ cm^-2 s^-1, which corresponds to an average of around 200 inelastic proton-proton collisions per beam-crossing (every 25 ns). To cope with these conditions, the ATLAS Inner Detector will be replaced by a new all-silicon system — the Inner Tracker (ITk). The ITk will be operational for more than ten years, during which time ATLAS is expected to record approximately 4000 fb^-1 of data. The ITk's pixel sub-system is based on hybrid pixel modules with new silicon sensors and readout chips. These studies focus on testbeam campaigns undertaken to study the spatial resolution and efficiencies of hybrid pixel detector modules based on the first large-structure prototype front-end readout chip — the RD53A — using planar silicon sensors. These devices have been irradiated to replicate the effect of the high radiation environment present during operation in the ATLAS detector. Results for devices using sensors with different punch-through bias structures and using different readout modes are summarised. Those with sensors incorporating a punch-through bias structure are found to exhibit systematically lower efficiency than those without, as a result of local areas of relative inefficiency around the punch-through dots. Despite this, all devices measured are found to satisfy the requirement of 97% efficiency at V_bias = 400 V after being irradiated to end-of-life fluence.

Hefei Advanced Light Facility (HALF) is a VUV and soft X-ray diffraction-limited storage ring, which uses a modified hybrid multi-bend achromat (HMBA) lattice. In a HMBA lattice, many nonlinear effects are cancelled by the -I transformation between sextupoles. But for amplitude-dependent tune shifts (ADTS) and high-order chromaticities, generally they cannot be controlled well, which will limit the dynamic aperture and momentum aperture. To further improve the performance of the HALF lattice, linear parameters and nonlinear dynamics are optimized in this paper. First, linear lattice, ADTS and second-order chromaticity are simultaneously optimized with magnet strengths varied in large ranges to better explore good solutions. In this optimization, lattice solutions with both low emittances and relatively good nonlinear dynamics are efficiently obtained. Then, starting from the good solution region generated above, direct optimization of dynamic aperture and Touschek lifetime based on particle tracking is performed. After this second optimization, the lattices with larger DAs and longer lifetimes are obtained for HALF. This method can also be used for optimizing other HMBA lattices.

The use of high-Z sensors for scientific applications at synchrotrons will gain more importance due to the upgrade of many light sources around the world to diffraction limited light sources for which the photon flux at high photon energies (above 30 keV) will significantly increase. Especially when illuminated with high photon fluxes, many established high-Z sensor materials like GaAs or Cd(Zn)Te are known to suffer from charge (de-)trapping effects in the bulk or at the contact interface which will ultimately lead to polarization and afterglow effects in the sensor. Commercially available high-Z sensors (Chromium-compensated GaAs, CdTe and CdZnTe) have been investigated at the Material Science beamline of the Swiss Light Source regarding their dynamic behavior when exposed to photon fluxes between 10⁶ ph/mm²·s and ≈ 5·10¹⁰ ph/mm²·s. In this work, the signal stability during irradiation will be presented, and a follow-up publication will discuss the afterglow.

The ICARUS liquid argon time projection chamber (LArTPC) neutrino detector has been taking physics data since 2022 as part of the Short-Baseline Neutrino (SBN) Program. This paper details the equalization of the response to charge in the ICARUS time projection chamber (TPC), as well as data-driven tuning of the simulation of ionization charge signals and electronics noise. The equalization procedure removes non-uniformities in the ICARUS TPC response to charge in space and time. This work leverages the copious number of cosmic ray muons available to ICARUS at the surface. The ionization signal shape simulation applies a novel procedure that tunes the simulation to match what is measured in data. The end result of the equalization procedure and simulation tuning allows for a comparison of charge measurements in ICARUS between Monte Carlo simulation and data, showing good performance with minimal residual bias between the two.

This paper reports on a measurement of electron-ion recombination in liquid argon in the ICARUS liquid argon time projection chamber (LArTPC). A clear dependence of recombination on the angle of the ionizing particle track relative to the drift electric field is observed. An ellipsoid modified box (EMB) model of recombination describes the data across all measured angles. These measurements are used for the calorimetric energy scale calibration of the ICARUS TPC, which is also presented. The impact of the EMB model is studied on calorimetric particle identification, as well as muon and proton energy measurements. Accounting for the angular dependence in EMB recombination improves the accuracy and precision of these measurements.

We present a programmable 16 channel, mixed signal, low power readout ASIC, having the project historically named Gigasample Recorder of Analog waveforms from a PHotodetector (GRAPH). It is designed to read large aperture single photon imaging detectors using micro channel plates for charge multiplication, and measuring the detector's response on crossed strips anodes to extrapolate the incoming photon position. Each channel consists of a fast, low power and low noise charge sensitive amplifier, which provides a myriad of coarse and fine programmable options for gain and shaping settings. Further, the amplified signal is recorded using, to our knowledge novel, the Hybrid Universal sampLing Architecture (HULA) ADC. A kind of mixed signal double buffer memory, that enables concurrent waveform recording, and selected event digitized data extraction. The sampling frequency is freely adjustable between few kHz up to 125 MHz, while the chip's internal digital memory holds a history 2048 samples for each channel, with a digital headroom of 12 bits. An optimized region of interest sample-read algorithm allows to extract the information just around the event pulse peak, while selecting the next event, thus substantially reducing the operational dead time. The chip is designed in 130 nm TSMC CMOS technology, and its power consumption is around 47 mW per channel.

Collective effects are important in the physics design of electron storage rings, especially for the fourth-generation synchrotron light source, where the collective effects are more severe than before and limit maximum stored beam current. To estimate beam collective effects, besides theoretical analysis, numerical tracking methods are necessary for obtaining more accurate and comprehensive results. To systematically study the comprehensive influence of wakefields and various damping mechanisms, we developed a new code Storage Ring Collective Effects Simulator (SRCES), which is a tracking code based on macroparticle model in 6-dimensional phase space. Several models are employed to handle various processes of particle motion. The modified transfer matrix and high order Taylor transfer map are used to solve particle motion under external electro-magnetic fields. A simplified equivalent damping and excitation model is used to represent the effects of synchrotron radiation on particle motion. The kick model is used to represent the influence of wakefields and RF cavity. Furthermore, the wake function data can be input as numerical arrays directly or through specific impedance models. In this paper, we describe the basic theory foundation, functions and benchmarked results of the code SRCES. Then, SRCES is used to conduct preliminary research on the collective effects of the Hefei Advanced Light Facility storage ring.

CuboDAQ is a custom data acquisition system to read out SiPM-based detectors. It features electronic boards to digitize the SiPMs signal, an FPGA-based system-on-module board, the connectivity to transmit the data to a central server, and all the software necessary to operate them. The front-end is based on the TOFPET2 ASIC, produced by PETsys, connected to a custom board, featuring an Enclustra Mercury SA1 module with a Cyclone V FPGA. Multiple boards can be operated synchronously by distributing the clock and synchronous reset signals from a central source. The system features a complete software framework to calibrate and monitor the detectors, to acquire and process data and to perform track reconstruction. The CuboDAQ system performance has been evaluated in different scenarios and can cope with sustained rates of above 4·10⁶ hits/s, with peaks of more than 7·10⁶ hits/s. This system has been employed for the readout of the SND@LHC detector at CERN, a testbeam telescope and lab setups.

Correlated photon calibration based on spontaneous parametric down-conversion (SPDC) provides a highly precise means to calibrate the detection efficiency of avalanche photodiode (APD). During the calibration process of detection efficiency via SPDC, precise measurement of the arrival time of correlated photons and accurate photon counting are essential. To achieve this goal, a data acquisition (DAQ) system with low-dead-time, high-resolution Time-to-Digital Converter (TDC) was designed in this paper. This TDC is designed based on tapped delay line (TDL), which is implemented on Xilinx Kintex-7 series field programmable gate array (FPGA). This TDC can accurately measure the time of arrival of input signals. Upon arrival of a photon signal, the TDC rapidly generates a timestamp to record the arrival time of the photon signal. Utilizing these timestamps, time delay and accurate measurements of time intervals can be achieved. The specially designed TDC input stage structure and encoding algorithm enable the alternating propagation and sampling of `01' and `10' transitions on TDL. Coupled with a pipelined architecture, the TDC's dead time is close to one clock cycle, which is 2.33 ns in the current implementation version. The structure of mode recognition and triggering ensures that the TDC can correctly calibrate time measurements and count photon counts. Experimental results show that the TDC achieves an RMS precision of better than 11.08 ps, and this measurement precision is maintained over long time intervals (0–10 us). The reliability of this DAQ for photon counting has been verified through standard signal sources.

Photomultiplier Tubes (PMTs) employing micro-channel plate (MCP) are a type of light-detection device designed for weak-light conditions. The MCP multiplication structure has advantage over traditional dynode structures due to its superior temporal resolution and immunity to magnetic interference. The application of atomic layer deposition (ALD) technology has significantly enhanced the longevity of MCP-PMTs. Additionally, the collection efficiency (CE) of MCP-PMTs is increased by coating the upper surface with high secondary-electron emission materials. However, tails on charge and transit time distribution are also observed which deteriorate the charge and time resolution of the MCP-PMT. This can be explained by the existance of the pre-multiplication events and elastically recoiled events. In this paper, the waveforms for four types of MCP-PMTs are analyzed, including the 20-inch MCP-PMT for JUNO, the 20-inch lotus-like MCP-PMT for LHAASO, the 2-inch 8×8-anodes MCP-PMT and the 1-inch single-anode MCP-PMT. Under single-photon detection environment, the full width at tenth maximum (FWTM) is found to be an efficient parameter to realize the distinction of the tails from the normal events for the 20-inch MCP-PMT. For the small-sized FPMT, the origins for the tails in TT distribution is also analyzed.

nEDMSF aims to measure the neutron electric dipole moment (d_n) with unprecedented precision. In this paper we explore the experiment's sensitivity when operating with an implementation of the critical dressing method in which the angle between the neutron and Helium-3 spins (ϕ_3n) is subjected to a square modulation by an amount ϕ_d (the "dressing angle"). Several parameters can be tuned to optimize sensitivity. We find roughly 10% improvement over a previous estimate, resulting primarily from the addition of a waiting period between the π/2 pulse that initiates d_n-driven ϕ_3n growth and the start of ϕ_3n modulation. We find negligible further improvement by allowing ϕ_d to vary continuously over the course of a run, and no degradation resulting from the addition of an in situ background measurement into each ϕ_3n modulation sequence. A complete simulation confirms a 300 live-day sensitivity ofσ = 1.45×10^-28e ·cm. At this level of sensitivity, σ_ϕ3n0 = 1 mrad precision on the initial n/³He angle difference is not negligible.

We study effects of transients on the beam transport in the SARAF Low Energy Beam Transport (LEBT) section. Beam signals from a collimator and a beam blocker at the LEBT exit were used for deducing the evolution of space charge neutralization during the beam pulse transport. The neutralization buildup time and final neutralization level were obtained. In the future, the impact of the varying neutralization level on the beam propagation downstream in the linac will be investigated.

Setups have been developed and constructed to study the main scintillation properties, such as light yield and emission kinetics, of liquid organic scintillators used in neutrino physics and astroparticle physics experiments. The measurement results of the main characteristics of these setups are presented in this work.

The influence of detector setup configuration and scintillator material choice on spectrum quality in Positron Annihilation Lifetime Spectroscopy (PALS) is fundamentally acknowledged primarily by empirical observation. However, this study quantifies the effects of ultra-fast plastic scintillators (BC422Q) within a conventional collinear (180-degree) detector setup used in the laboratory using the Geant4 simulation toolkit. We examine the impact of the scintillator's dimension and geometry (truncated cone vs. cylinder) on the detection efficiency for specific gamma-ray energies (1274 keV and 511 keV) and their proportion of corrupt events such as backscattering or multiple detections. Results indicate that the selection of scintillator dimension and shape significantly enhances detection efficiency albeit with an increase in corrupt events. Furthermore, we investigate the influence on the instrument response function (IRF) of the scintillators, showing how truncated cones offer superior precision and, thus, a narrower IRF compared to cylindrical shapes. Additionally, the effect of the sample material itself, in the case of a truncated cone as the scintillator shape, on the scintillator response was studied. It is observed that with an increasing atomic number of the sample the detection efficiency substantially decreases while the proportion of corrupt events also diminishes. Despite the sample material's influence on the energy of gamma-quanta interacting with the scintillator, no measurable impact on the IRF was detected for the chosen windows of the pulse height spectra. This investigation encourages a profound examination of the influences on spectrum quality in PALS measurements using Geant4 as a simulation tool highlighting the critical balance between detection efficiency and corrupt event frequencies.

In the upcoming upgrade project of the China Spallation Neutron Source (CSNS II), the beam power is planned to increase to 500 kW. One important potential application with the enhanced beam power is the proton radiography based on resonance extraction of the proton beams. In this article we present a scheme of beam resonance extraction for the proton radiography, by using the skew sextupole magnet, the trim quadrupoles(QTs), the rf kicker, and the septum magnet in the rapid cycling synchrotrons (RCS) of the CSNS II. It is shown that with the adoption of the proposed scheme, a sufficient large number of particles 1.0 × 10¹⁰ in 20 bunches with 410 ns time interval can be extracted from the RCS, which satisfies the requirement of the proton radiography.

During the pulsed operation of the linear accelerator in Dalian Coherent Light Source (DCLS), we observe a strong correlation between the klystron modulator's high voltage and the klystron output microwave, with noticeable stratification among microwaves. Therefore, we propose an intra-pulse feedforward algorithm and implement it in Low-Level Radiofrequency (LLRF) systems. This algorithm assumes that the transfer model of the microwave system is linear within a small range of work points and measures the transfer coefficient of the microwave between the LLRF and klystron. For each pulsed microwave of the klystron output, the LLRF system first calculates the vector deviation between the initial measurement within its pulse and the target. The deviation will be compensated in the LLRF excitation so that the stratification in the later part of the pulsed microwave is suppressed. Experiments have shown that this algorithm can effectively suppress the stratification among microwaves. The microwave amplitude and phase stability (RMS) are improved from 0.10%/0.19^∘ to 0.07%/0.06^∘ (klystron 4, for example), and the beam energy stability is significantly enhanced from 0.14% to 0.08%. This algorithm can also be applied to other FEL accelerators operating in pulsed modes.

Transverse Deflecting Cavities (TDCs) are generally adopted for electron beam diagnosis. Three sets of S-band and two sets of X-band TDCs are planned at Shenzhen Superconducting Soft X-ray Free Electron Laser (S³FEL) to accurately measure the temporal distribution of ultra-short electron bunches. The microwave system of one TDC consisting of a Low-Level Radio-Frequency system (LLRF), a solid-state amplifier, a klystron, and several waveguide couplers is operated in pulse mode with a maximum repetition rate of 50 Hz. Its microwave stabilities for amplitude and phase are required to be better than 0.05%/0.05^∘ (RMS). This article will introduce the prototype design of the hardware, firmware, and software of the digital LLRF system for S-band TDCs. We use a homemade local oscillator and commercial cards based on the MicroTCA standard in hardware design. The firmware design will use an IQ demodulation and a reference-tracking algorithm to eliminate the measurement noise and drift. The software design is based on the Experimental Physics and Industrial Control System (EPICS), achieving data acquisition, slow control, and interface display functions. This technical report will also show some preliminary test results.

In this report, we propose a simple way how considerably improve the performance of the gas stripper setup at the GSI Universal Linear Accelerator (UNILAC) in Germany. In our proposed approach, we replace inside the main GSI stripper chamber the current nozzle and the short windowless storage gas cell (for the pulsed gas jet operation mode) with a simple conical diverging nozzle combined with a gas catcher tube placed on the gas jet axis at some distance downstream from the nozzle exit. As a result, the background pressure in the main and differentially pumped adjacent vacuum chambers of the gas stripper at the GSI UNILAC dramatically reduces, making it possible to achieve the required optimal thickness of the gas targets. The pulsed gas stripper operation is realized by implementing a commercially available fast gas valve connected to the nozzle entrance. Moreover, the ion beam pulse repetition rate can be increased, allowing for a considerably higher average intensity of the ion beams extracted from the GSI UNILAC. We explored the performance of the proposed GSI UNILAC gas stripper modification by means of detailed computer experiments, which provide a realistic description of supersonic gas jets flowing out of the nozzle into the vacuum. The results of these computer experiments have presented and discussed.

This paper describes the GEANT4 simulation results of a wavelength shifting (WLS) fiber-based γ detector, which is the fundamental detection unit within arrayed radiation portal monitors. The structure of the detector unit consists of a plastic scintillator, a wavelength shifting fiber, and a silicon photomultipliers (SiPM), which is low cost and miniaturization. The WLS fiber is spirally coiled at the plastic scintillator's backside, which can be used for photon collection and transmission. Besides SiPMs are attached to both ends of WLS fiber for photons detection and photoelectric conversion. To further optimize the detector performance, the simulations of scintillation photon generation and transport within the detector were conducted using GEANT4 software. The investigation focused on the effects of the bending radius, pitch, and length of the WLS fibers on photon collection and transport efficiency. Furthermore, the study has examined the impact of plastic scintillator size on photon output and the uniformity of detector response. The results demonstrate that when the plastic scintillator is 25 cm× 25 cm× 5 cm and the WLS fibers are coiled with a minimum radius of 35 mm and a pitch of 10 mm, the detector exhibits a high photon output and good response uniformity. Moreover, embedding the fibers within the plastic scintillator yields a higher light output than coupling them on the surface of the plastic scintillator.

A new multitube position-sensitive detector (PSD) for small-angle neutron scattering spectrometer at the Chinese Mianyang Research Reactor was assembled in 2021. This paper presents the experimental design and implementation aimed at noise reduction, spatial resolution testing, and position correction for the multitube PSD. In addition, the analysis results indicate that the deviation of the linear fitting correction increases linearly with the gain difference between the two ends of the PSD, ultimately hindering effective position correction. To address this issue, a new position correction method for multitube PSDs has been proposed that is simpler, more accurate, and broadly applicable to similar detectors.