IEEE Transactions on Nuclear Science最新文献

{"title":"A Novel Segment-Based HLT Tracking Algorithm for High-Occupancy and Complex Environments at the Super Tau-Charm Facility","authors":"Pengkun Jia;Zhujun Fang;Hang Zhou;Yuhe Huang;Changqing Feng;Jianbei Liu","doi":"10.1109/TNS.2026.3726696","DOIUrl":"https://doi.org/10.1109/TNS.2026.3726696","url":null,"abstract":"The Super Tau-Charm Facility (STCF) is a next-generation electron-positron collider designed to operate at a center-of-mass energy of 2–7 GeV and a luminosity of <inline-formula> <tex-math>$0.5times 10^{35}$ </tex-math></inline-formula> cm⁻² s⁻¹ at 4 GeV. Its high luminosity environment poses a challenge for the high-level trigger (HLT) tracking in the main drift chamber (MDC): achieving the expected physics performance under elevated detector occupancy while maintaining a sustainable computing latency. The HLT is implemented on a software platform, handling the most complex tasks in the trigger systems of collider experiments. High occupancy increases the complexity of segment graph traversal, resulting in longer computing latency. To address this issue, a novel HLT tracking algorithm based on track segments is proposed. The algorithm constructs a pattern bank comprising 11 pre-defined patterns to enable fast segment classification. The edge matrix recording segment connections is optimized using position, momentum, and timing criteria to suppress incorrect links, and stereo superlayer segments are merged to improve track consistency. These measures significantly reduce the number of stored segments and the size of the edge matrix, thereby lowering the complexity of global tracking. Even at 25% occupancy, the number of elements for global tracking is reduced to approximately 400–500, while the edge matrix density remains below 1%. Using depth-first search (DFS) within connected components, the algorithm maintains stable performance for occupancies ranging from 5% to 25%, achieving a background hit rejection of approximately 75% to 30%. Validation against the STCF offline reconstruction confirms that the proposed HLT algorithm preserves high signal hit efficiency without significantly degrading offline tracking efficiency or reconstruction precision. While maintaining high signal hit efficiency and tracking stability across a wide range of occupancies, the algorithm has a typical computing latency of approximately 200 ms per event at 8% occupancy, which is comparable to the hundreds of milliseconds typically consumed by tracking in large-volume gaseous detectors. Suppressing this latency is the key focus of the next stage.","PeriodicalId":13406,"journal":{"name":"IEEE Transactions on Nuclear Science","volume":"73 9","pages":"3518-3534"},"PeriodicalIF":2.4,"publicationDate":"2026-09-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"148974690","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Charge Collection Efficiency in a Novel Graphene-Optimized Silicon Carbide Detector Under 160 keV X-Ray Irradiation","authors":"Yingjie Huang;Congcong Wang;Jingxuan He;Yi Zhan;Zhenyu Jiang;Xiyuan Zhang;Xin Shi","doi":"10.1109/TNS.2026.3727278","DOIUrl":"https://doi.org/10.1109/TNS.2026.3727278","url":null,"abstract":"A novel graphene-optimized silicon carbide (SiC) p-i-n detector was fabricated. Its electrical properties, charge collection performance, and signal rise time were evaluated under non-irradiated conditions and under X-ray irradiation with an energy of 160 keV at doses of 0.1 and 1 MGy. The leakage current density and effective doping concentration remain virtually unchanged after irradiation, with values of approximately <inline-formula> <tex-math>$3.6~mathrm {nA/cm^{2}}$ </tex-math></inline-formula> and <inline-formula> <tex-math>$8.08 times 10^{13}~text {cm}^{-3}$ </tex-math></inline-formula>, respectively. The rise times of the signals from <inline-formula> <tex-math>$alpha $ </tex-math></inline-formula> particles detected by the detector under unirradiated, 0.1 MGy, and 1 MGy X-ray irradiation conditions are 336, 368, and 387 ps, respectively. After 0.1 and 1 MGy X-ray irradiation, the charge collection efficiencies of the detector for <inline-formula> <tex-math>$alpha $ </tex-math></inline-formula> particles are 97.69% and 95.00%, respectively. Experiments confirm that 160-keV X-ray irradiation induces virtually no displacement damage in 4H-SiC, and the minor degradation in device performance can be primarily attributed to the slight surface oxidation of the graphene layer induced by X-ray exposure. Nevertheless, the graphene-optimized SiC p-i-n detector as a whole exhibits excellent charge collection performance and a fast signal response. These results demonstrate stable performance under extreme X-ray exposure, highlighting the detectors’ potential for radiation-hard applications in high-energy physics, space missions, and nuclear reactor monitoring.","PeriodicalId":13406,"journal":{"name":"IEEE Transactions on Nuclear Science","volume":"73 9","pages":"3752-3757"},"PeriodicalIF":2.4,"publicationDate":"2026-09-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"148974718","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Analysis of Low-Altitude NEMP Propagation Characteristics During Day--Night Transition","authors":"Zhaomin Li;Xinbo He;Bing Wei;Jiarong Dong","doi":"10.1109/TNS.2026.3718899","DOIUrl":"https://doi.org/10.1109/TNS.2026.3718899","url":null,"abstract":"To address the lack of research on the propagation characteristics of low-altitude nuclear electromagnetic pulse (NEMP) in the day–night transition region of the Earth–ionosphere waveguide, this article establishes a waveguide model incorporating a nonuniform day–night transitional structure and investigates the propagation behavior of low-altitude NEMP within this environment. An efficient computation of the source-region fields for low-altitude NEMP is achieved by employing a prolate spheroidal–hyperbolic coordinate system, with further acceleration of computational performance through OpenMP parallelization. Due to the absence of a standardized waveform representation for low-altitude NEMP—unlike lightning electromagnetic pulse, which can be analytically modeled using a simple double-exponential function—this article incorporates the source-region contribution into the Earth–ionosphere propagation model containing a day–night transitional structure by means of the equivalence principle. Using the finite-difference time-domain (FDTD) method, the effects of diurnal environment, propagation direction, ground medium, and explosion yield on signal propagation are analyzed. This study provides a certain reference for analyzing the propagation of low-altitude NEMP in the ionospheric transition region.","PeriodicalId":13406,"journal":{"name":"IEEE Transactions on Nuclear Science","volume":"73 9","pages":"3689-3698"},"PeriodicalIF":2.4,"publicationDate":"2026-09-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"148974746","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Neutron/X-Ray Dual-Modality Tomography at ERNI: A Case Study on Cultured Pearls","authors":"Xin Shu;Shengxiang Wang;Xin Ge;Jiancong Li;Le Dong;Jie Chen","doi":"10.1109/TNS.2025.3640240","DOIUrl":"https://doi.org/10.1109/TNS.2025.3640240","url":null,"abstract":"X-ray and neutron computed tomography (CT) are widely used for nondestructive characterization of internal structures. Their distinct contrast mechanisms, arising from different interactions with matter, can enhance structural analysis when combined. In this study, we performed X-ray and neutron CT experiments on cultured pearl samples using the energy-resolved neutron imaging (ERNI) instrument at China Spallation Neutron Source (CSNS). A multistep registration pipeline based on edge extraction and rigid 3-D transformation was developed to align and fuse the datasets. The results demonstrate the potential of dual-modality imaging for enhanced structural visualization of materials with complex internal structures.","PeriodicalId":13406,"journal":{"name":"IEEE Transactions on Nuclear Science","volume":"73 9","pages":"3715-3722"},"PeriodicalIF":2.4,"publicationDate":"2026-09-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"148974689","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"GPU-Accelerated Analytic Simulation of Sparse Ionization Signal Formation in Pixelated Time Projection Detector","authors":"Yousen Zhang;Brett Viren;Mary Bishai;Sergey Martynenko;Xin Qian;Rado Razakamiandra;Brooke Russell","doi":"10.1109/TNS.2026.3720521","DOIUrl":"https://doi.org/10.1109/TNS.2026.3720521","url":null,"abstract":"This article presents a GPU-accelerated simulation package, <monospace>TRED</monospace>, for next-generation neutrino detectors with pixelated charge readout, leveraging community-driven software ecosystems to ensure adaptability and extensibility. We introduce two generic contributions: 1) an effective-charge representation based on Gaussian quadrature rules, in which the linear-interpolation factors for the field response inside each voxel are absorbed into the effective charge, and 2) a sparse, block-binned tensor representation that enables efficient FFT-based computation of induced signals on readout electrodes for sparsely activated detector volumes. The former captures structure inside a voxel without dense sampling, while the latter achieves low memory usage and scalable runtime, as demonstrated in benchmark studies. The underlying data representation applies to large-scale detectors and to other computational problems involving sparse activity.","PeriodicalId":13406,"journal":{"name":"IEEE Transactions on Nuclear Science","volume":"73 9","pages":"3505-3517"},"PeriodicalIF":2.4,"publicationDate":"2026-09-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"148974703","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Research on Multiparameter Self-Tuning of Digital Low-Level RF System Based on Reinforcement Learning","authors":"Kai Guo;ZheXin Xie;ZhenCheng Mu;HeXin Wang;Hui Zhang;LinYan Rong;MaLiang Wan;Bo Wang","doi":"10.1109/TNS.2026.3713298","DOIUrl":"https://doi.org/10.1109/TNS.2026.3713298","url":null,"abstract":"To ensure the efficient operation of the upgraded digital low-level radio frequency (LLRF) system of the CSNS-II linear accelerator under higher precision and larger scale conditions, this study employs reinforcement learning (RL) algorithms to train an agent for autonomous optimization of LLRF control parameters. First, two RL algorithms, proximal policy optimization (PPO) and soft actor–critic (SAC), were trained, respectively, within the established LLRF simulation model to compare their efficiency and accuracy in LLRF parameter optimization. The study demonstrates that, benefiting from its off-policy nature, the SAC algorithm outperforms PPO in terms of data utilization efficiency and convergence speed, and is thus selected as the baseline algorithm for agent training. Subsequently, validation experiments based on the SAC algorithm were conducted on the China Spallation Neutron Source (CSNS) buncher cavity, where the trained agent successfully achieved autonomous closed-loop control parameter optimization, meeting the expected control objectives.","PeriodicalId":13406,"journal":{"name":"IEEE Transactions on Nuclear Science","volume":"73 9","pages":"3494-3504"},"PeriodicalIF":2.4,"publicationDate":"2026-09-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"148974711","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Localization of Radioactive Sources by Multimodal Imaging Using a Single Gamma Camera","authors":"Kamel Benmahi;Vincent Schoepff;Guillaume Amoyal;Frédérick Carrel;Johann Plagnard;Jean-Michel Bourbotte","doi":"10.1109/TNS.2024.3389654","DOIUrl":"10.1109/TNS.2024.3389654","url":null,"abstract":"In the nuclear industry, localizing and visualizing radioactive hot spots is crucial, with applications spanning decommissioning, waste management, radiology in nuclear medicine, and homeland security. Gamma imaging offers a solution for remote localization and visualization of radioactive hot spots. Based on Timepix3 technology, our gamma imaging system can deploy two different imaging modalities: coded aperture (CA) and Compton imaging. This research introduces a combined approach, referred to as multimodal imaging, validated through Monte-Carlo (MC) simulations and experiments using a Timepix3 technology coupled with a rank 7 modified uniformly redundant array (MURA) CA. One of the goals of such an imager is to incorporate both techniques’ advantages into a single system while also minimizing their respective drawbacks. Adding multiple sources of information for the localization of radioactive hot spots presents various opportunities to enhance the algorithms used in gamma image reconstruction. Furthermore, the overall system is designed to be portable and compact to ease its field use.","PeriodicalId":13406,"journal":{"name":"IEEE Transactions on Nuclear Science","volume":"73 9","pages":"3791-3798"},"PeriodicalIF":2.4,"publicationDate":"2026-09-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140614343","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"IEEE Transactions on Nuclear Science Publication Information","authors":"","doi":"10.1109/TNS.2026.3730563","DOIUrl":"https://doi.org/10.1109/TNS.2026.3730563","url":null,"abstract":"","PeriodicalId":13406,"journal":{"name":"IEEE Transactions on Nuclear Science","volume":"73 9","pages":"C2-C2"},"PeriodicalIF":2.4,"publicationDate":"2026-09-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://ieeexplore.ieee.org/stamp/stamp.jsp?tp=&arnumber=11693474","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"148974695","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Time Resolution of a 4H-SiC PIN Detector Irradiated With 16 MeV/u Ta Ions","authors":"Jingxuan He;Congcong Wang;Yi Zhan;Zhenyu Jiang;Xiyuan Zhang;Xin Shi;Kai Liu","doi":"10.1109/TNS.2026.3715517","DOIUrl":"https://doi.org/10.1109/TNS.2026.3715517","url":null,"abstract":"A silicon carbide (SiC) PIN detector was fabricated, and its radiation tolerance under Ta heavy ion irradiation of 16 MeV/u was evaluated. Its electrical properties and time resolution for <inline-formula> <tex-math>$beta $ </tex-math></inline-formula>-particles (⁹⁰Sr) are reported. Experimental results demonstrate that for the unirradiated and irradiated 4H-SiC PIN detectors, the leakage current remains on the order of pA. The effective doping concentration of the lightly doped 4H-SiC epitaxial layer is about (5–6)<inline-formula> <tex-math>$times {,}10^{13}~mathrm {cm}^{-3}$ </tex-math></inline-formula>, approaching the lower limit of SiC epitaxial growth technology. Full depletion voltages of the 4H-SiC PIN detectors are consistently measured to be approximately 120 V–130 V. No significant changes in the leakage currents, depletion voltage, and effective doping concentrations were observed between the unirradiated and irradiated 4H-SiC PIN detectors. The 4H-SiC PIN detector exhibits only a minor degradation in time resolution (from 38.1 to 53.4 ps) under medium-fluence heavy-ion irradiation. This indicates that the 4H-SiC detector exhibits a certain degree of resistance to medium-fluence Ta heavy ion irradiation. These results demonstrate stable performance under Ta heavy ion irradiation, highlighting the detector’s potential for radiation-hard applications in high-energy physics, space missions, and nuclear reactor monitoring.","PeriodicalId":13406,"journal":{"name":"IEEE Transactions on Nuclear Science","volume":"73 9","pages":"3767-3772"},"PeriodicalIF":2.4,"publicationDate":"2026-09-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"148974678","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"A 300 krad(Si) TID Tolerant Dual-Direction SCR With nA-Level Leakage and High Holding Voltage for Space Communication Buses","authors":"Yujie Liu;Wei Liu;Zhixiang Cao;Xiangliang Jin","doi":"10.1109/TNS.2026.3722730","DOIUrl":"https://doi.org/10.1109/TNS.2026.3722730","url":null,"abstract":"The reliability requirements for on-chip electrostatic discharge (ESD) protection in high-voltage communication buses for space applications are extremely stringent. Traditional ESD solutions do not effectively meet the requirements for high holding voltage (<inline-formula> <tex-math>$V_{mathrm {h}}$ </tex-math></inline-formula>) and total-ionizing-dose (TID) tolerance in these applications. Therefore, this article proposes a TID tolerant dual-direction silicon-controlled rectifier (DDSCR) based on a 0.18-<inline-formula> <tex-math>$mu $ </tex-math></inline-formula>m BCD process, which is suitable for high-voltage radiation environments. At the same size, the <inline-formula> <tex-math>$V_{mathrm {h}}$ </tex-math></inline-formula> (15.3 V) of the embedded bipolar junction transistor (BJT) shunt DDSCR (EBSDDSCR) is higher than that of the embedded MOS shunt DDSCR (EMSDDSCR). Furthermore, when the TID reaches 300 krad(Si), the EBSDDSCR effectively blocks the sidewall leakage path, maintains a low leakage current, and does not significantly degrade ESD performance. The results indicate that, compared to other high-voltage ESD structures, the EBSDDSCR exhibits superior characteristics, including higher <inline-formula> <tex-math>$V_{mathrm {h}}$ </tex-math></inline-formula>, improved human body model (HBM) protection level, higher TID tolerance, and lower leakage current. It can serve as a promising candidate for on-chip ESD protection in aerospace high-voltage communication buses.","PeriodicalId":13406,"journal":{"name":"IEEE Transactions on Nuclear Science","volume":"73 9","pages":"3662-3669"},"PeriodicalIF":2.4,"publicationDate":"2026-09-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"148974724","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}