Dóra Erzsébet Veres , Massimo Giovannozzi , Giuliano Franchetti
{"title":"An innovative method for slow extraction in circular hadron accelerators with resonance islands and bent crystals","authors":"Dóra Erzsébet Veres , Massimo Giovannozzi , Giuliano Franchetti","doi":"10.1016/j.nima.2025.170286","DOIUrl":"10.1016/j.nima.2025.170286","url":null,"abstract":"<div><div>Recent developments in accelerator physics and nonlinear beam dynamics have broadened the range of techniques for manipulating charged-particle beams. The effective use of adiabatic trapping and beam transport in resonance islands within the CERN Proton Synchrotron has been the basis for multiturn extraction. Moreover, the effective deployment of bent crystals in the CERN Large Hadron Collider has improved the efficiency of the collimation system and within the CERN Super Proton Synchrotron, it has significantly minimised losses at the extraction septum during slow extraction. We discuss the potential synergy of using resonance islands and bent crystals together to create a novel approach for slow extraction in circular hadron accelerators.</div></div>","PeriodicalId":19359,"journal":{"name":"Nuclear Instruments & Methods in Physics Research Section A-accelerators Spectrometers Detectors and Associated Equipment","volume":"1073 ","pages":"Article 170286"},"PeriodicalIF":1.5,"publicationDate":"2025-02-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143394663","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
C.L. Stewart , B.L. Goldblum , R.G. Abbott , L. Appleby , B.J. Borghetti , V. Hollingshead , J.H. Whetzel
{"title":"Machine learning for reactor power monitoring with limited labeled data","authors":"C.L. Stewart , B.L. Goldblum , R.G. Abbott , L. Appleby , B.J. Borghetti , V. Hollingshead , J.H. Whetzel","doi":"10.1016/j.nima.2025.170285","DOIUrl":"10.1016/j.nima.2025.170285","url":null,"abstract":"<div><div>Real-time reactor power monitoring is critical for a variety of nuclear applications, spanning safety, security, operations, and maintenance. While machine learning methods have shown promise in monitoring reactor power levels, there is limited research on their efficacy in label-starved environments. The goal of this work is to assess the feasibility of classifying nuclear reactor power level using multisource data in scenarios with limited labels. Data were collected using low-resolution multisensors at four nuclear reactor facilities: two large research reactors and two TRIGA reactors. Within each pair, one reactor dataset served as the source and the other as the target in a transfer learning paradigm. Twenty-three supervised models were trained on labeled sequences of magnetic field and acceleration data from each of the target sites. Self-learning and transfer learning methods were applied to the top performing models to assess their classification performance with increasing amounts of labeled data. While reactor power level classification was achieved with a Matthews Correlation Coefficient of up to 0.739 ± 0.003 and 0.622 ± 0.009 with only 400 sequences per power state for the large research reactor and TRIGA target sites, respectively, self-learning and transfer learning leveraging source site data did not improve target classification performance. These findings suggest that alternative methods, such as higher sensitivity sensors, digital twins, or the use of physics-informed models, are required to enable high-performance classification in machine learning approaches to reactor monitoring with a dearth of target ground truth.</div></div>","PeriodicalId":19359,"journal":{"name":"Nuclear Instruments & Methods in Physics Research Section A-accelerators Spectrometers Detectors and Associated Equipment","volume":"1073 ","pages":"Article 170285"},"PeriodicalIF":1.5,"publicationDate":"2025-02-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143377627","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
R. Mondal Saha , K. Banerjee , A. Chakraborty , N. Gayathri , Satya Samiran Nayak , Souvik Jana , G.R. Umapathy , R. Shil , Anirban Basak , S. Bhattacharyya , Satyajit Hazra , Saif Ahmad Khan
{"title":"Preparation of selenium target using sedimentation method for in-beam γ-ray spectroscopic measurement","authors":"R. Mondal Saha , K. Banerjee , A. Chakraborty , N. Gayathri , Satya Samiran Nayak , Souvik Jana , G.R. Umapathy , R. Shil , Anirban Basak , S. Bhattacharyya , Satyajit Hazra , Saif Ahmad Khan","doi":"10.1016/j.nima.2025.170288","DOIUrl":"10.1016/j.nima.2025.170288","url":null,"abstract":"<div><div>Natural and isotopically enriched selenium targets with a typical thickness of 6.8 mg/cm<span><math><msup><mrow></mrow><mrow><mn>2</mn></mrow></msup></math></span> were prepared using only 20 mg of powder, which was deposited on a Mylar backing through sedimentation process. The surface morphology of these targets was examined using scanning electron microscopy, while elemental analysis was conducted through <span><math><mi>X</mi></math></span>-ray photoelectron spectroscopy, energy-dispersive <span><math><mi>X</mi></math></span>-ray spectroscopy and <span><math><mi>X</mi></math></span>-ray diffraction technique. These analyses confirmed that the selenium retained its crystalline structure, with no elemental impurities other than carbon and oxygen. The presence of carbon and oxygen was mainly due to the polyvinyl alcohol used during fabrication. The thickness of the targets was measured via <span><math><mi>X</mi></math></span>-ray attenuation using a Germanium-based Low-Energy Photon Spectrometer. These targets were subsequently employed in ion-beam-induced <span><math><mi>γ</mi></math></span>-ray spectroscopic measurements to investigate the nuclear level structure of <span><math><msup><mrow></mrow><mrow><mn>81</mn><mo>,</mo><mn>82</mn></mrow></msup></math></span>Br. Even after five days of continuous beam exposure, the condition of the targets remained unchanged. X-ray diffraction analysis of the irradiated targets showed no significant changes in microstrain and crystallite size.</div></div>","PeriodicalId":19359,"journal":{"name":"Nuclear Instruments & Methods in Physics Research Section A-accelerators Spectrometers Detectors and Associated Equipment","volume":"1074 ","pages":"Article 170288"},"PeriodicalIF":1.5,"publicationDate":"2025-02-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143419355","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Yan Wang , Kun Jiang , Kaifeng Shen , Cheng Li , Zebo Tang , Wangmei Zha
{"title":"High-precision calibration of gain and characterization of single-photoelectron response in photomultiplier tubes","authors":"Yan Wang , Kun Jiang , Kaifeng Shen , Cheng Li , Zebo Tang , Wangmei Zha","doi":"10.1016/j.nima.2025.170269","DOIUrl":"10.1016/j.nima.2025.170269","url":null,"abstract":"<div><div>Accurate gain calibration of photomultiplier tubes is crucial because their fundamental function is to detect photon counts under low-light conditions. Traditional photomultiplier tube calibration methods require assumptions about the single photoelectron response in the charge spectrum, which are then used to construct the complete photomultiplier tube response function. However, discrepancies between these assumptions and actual single photoelectron responses can introduce calibration bias. This paper presents a novel method utilizing a joint analysis of charge and amplitude spectra. This approach enables precise calibration of the photomultiplier tube gain and provides an authentic single photoelectron response.</div></div>","PeriodicalId":19359,"journal":{"name":"Nuclear Instruments & Methods in Physics Research Section A-accelerators Spectrometers Detectors and Associated Equipment","volume":"1073 ","pages":"Article 170269"},"PeriodicalIF":1.5,"publicationDate":"2025-02-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143372223","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Jianming Zhang , Zhiwei Li , Jie Pang , Dikun Yang , Zhentao Yang , Zhongchang Chen , Guihua Long , Peng Du , Liping Huang , Tiantian Song , Kaidi Li , Menglin Cui , Feng Bao , Fang Liu , Yanhui Wang , Dongxiang Liu , Xiaoping Ouyang , Ran Han
{"title":"Muon absorption imaging for the density structure of metro tunnel overburden","authors":"Jianming Zhang , Zhiwei Li , Jie Pang , Dikun Yang , Zhentao Yang , Zhongchang Chen , Guihua Long , Peng Du , Liping Huang , Tiantian Song , Kaidi Li , Menglin Cui , Feng Bao , Fang Liu , Yanhui Wang , Dongxiang Liu , Xiaoping Ouyang , Ran Han","doi":"10.1016/j.nima.2025.170307","DOIUrl":"10.1016/j.nima.2025.170307","url":null,"abstract":"<div><div>Detecting the geological structure of the overburden above subway tunnels is crucial for the safe operation of the subway. Cosmic-ray muon, due to their strong penetration capabilities, offer a non-invasive method to probe underground structures. This study leverages muon absorption imaging technology to map the geological density variations of the overburden between Shenzhen Metro's Apollo South and Yuanshan Stations. A muon detector measured muon flux at 22 points within the tunnel, which, combined with preliminary geophysical drilling data, allowed for the estimation of average densities using the differential evolution global optimization algorithm. The results show that muon flux variations corresponded well with changes in marble content within the soil, reflecting density increases from 2.08 g/cm³ to 2.27 g/cm³ between measurement points 1 to 13, and decreases to 2.03 g/cm³ at points 14 and beyond due to river erosion effects. This study confirms the efficacy of muon absorption imaging in identifying density anomalies in tunnel overburden. By integrating prior geological information, the differential evolution algorithm enhances the precision and efficiency of stratification analysis. This novel approach offers significant potential for mitigating geological hazards and ensuring subway safety, with broader applications in other underground infrastructure and continuous monitoring systems. The findings could influence future standards in subway construction and operation, highlighting the importance of innovative methods in geological assessment and infrastructure safety.</div></div>","PeriodicalId":19359,"journal":{"name":"Nuclear Instruments & Methods in Physics Research Section A-accelerators Spectrometers Detectors and Associated Equipment","volume":"1073 ","pages":"Article 170307"},"PeriodicalIF":1.5,"publicationDate":"2025-02-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143394661","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
S. Weatherly , C. Jing , E. Wisniewski , D. Doran , J. Power , B. Freemire , T. Abe , T. Higo , D. Satoh
{"title":"Standing wave Dielectric Disk Accelerating structure design and low power measurements","authors":"S. Weatherly , C. Jing , E. Wisniewski , D. Doran , J. Power , B. Freemire , T. Abe , T. Higo , D. Satoh","doi":"10.1016/j.nima.2025.170283","DOIUrl":"10.1016/j.nima.2025.170283","url":null,"abstract":"<div><div>A Dielectric Disk Accelerator (DDA) is a metallic accelerating structure loaded with dielectric disks to increase coupling between cells, thus producing a high group velocity, while still maintaining a high shunt impedance. This is crucial for achieving high efficiency, high gradient acceleration in the short rf pulse acceleration regime. Recent research of these structures has produced traveling wave structures that are powered by very short (<span><math><mo>∼</mo></math></span>9 ns), very high power (400 MW) RF pulses using two beam acceleration at the Argonne Wakefield Accelerator Complex. In testing, these structures have withstood more than 320 MW of power and produced accelerating gradients of over 100 MV/m. A new standing wave DDA structure is being fabricated for testing on the Nextef2 test stand at KEK that will be powered by a more conventional, klystron power source. Simulation results of this structure show that at 50 MW of input power, the DDA produces a 457 MV/m gradient. It also has a large shunt impedance of 160 M<span><math><mi>Ω</mi></math></span>/m and an r/Q of 21.6 k<span><math><mi>Ω</mi></math></span>/m. Cold testing of this structure was conducted this summer showing a good match with the excited field but a significantly lower matching at the working frequency.</div></div>","PeriodicalId":19359,"journal":{"name":"Nuclear Instruments & Methods in Physics Research Section A-accelerators Spectrometers Detectors and Associated Equipment","volume":"1073 ","pages":"Article 170283"},"PeriodicalIF":1.5,"publicationDate":"2025-02-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143394695","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Renmu Zhang , Jun Wang , Lihua Wang , Biao Deng , Jun Hu
{"title":"Synchrotron based sparse-view CT artifact correction with STC-UNet","authors":"Renmu Zhang , Jun Wang , Lihua Wang , Biao Deng , Jun Hu","doi":"10.1016/j.nima.2025.170306","DOIUrl":"10.1016/j.nima.2025.170306","url":null,"abstract":"<div><div>Synchrotron radiation micro-CT imaging is widely used in various scientific fields as a 3D non-destructive imaging technique with high penetration, high resolution and high contrast. Roots According to the Shannon-Nyquist theorem, sufficient projection data need to be collected to obtain high-quality CT reconstructed slices. In order to improve the temporal resolution of CT, sparse data sampling methods have been proposed. However, images reconstructed from sparse view projections often have severe streak artifacts. In this paper, we propose an artifact correction method swin transformer and convolutional U-net (STC-Unet) for synchrotron sparse CT. The network is based on the structure of U-Net, which combines the local feature extraction capability of convolutional neural network and the global feature extraction capability of Transformer in the encoder part, and reduces the artifacts introduced by the single up-sampling by using a dual up-sampling module in the decoder part. The method is applied to sparse CT experiments on synchrotron radiation metal mesh samples, and the results show that the method has good results in removing artifacts while preserving structural details. Compared with other methods, the quantitative evaluation of our proposed model is significantly improved.</div></div>","PeriodicalId":19359,"journal":{"name":"Nuclear Instruments & Methods in Physics Research Section A-accelerators Spectrometers Detectors and Associated Equipment","volume":"1073 ","pages":"Article 170306"},"PeriodicalIF":1.5,"publicationDate":"2025-02-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143387689","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Application of a data-driven tomography method for the Gas Electron Multiplier (GEM) based X-ray camera on EAST","authors":"Y. Hu , E. Li , C. Ma , C. Mai","doi":"10.1016/j.nima.2025.170281","DOIUrl":"10.1016/j.nima.2025.170281","url":null,"abstract":"<div><div>A Gas Electron Multiplier (GEM) camera has been used for soft X-ray measurements on the Experimental Advanced Superconducting Tokamak (EAST), and the obtained data after a tomography calculation showed much useful information on the plasma macroscopic instabilities. A large experimental database has been built from the chord-integrated X-ray radiation signal measured by GEM, and we then develop a data-driven tomography method for fast viewing of X-ray emissivity profiles on the plasma cross-section. This tomography method is further applied in analyzing a plasma major disruption event, indicating there exists a vertical displacement event before a plasma current quench. This study suggests that the GEM camera with this fast data-driven tomography would be helpful for further feedback control of fusion plasmas to avoid plasma disruptions.</div></div>","PeriodicalId":19359,"journal":{"name":"Nuclear Instruments & Methods in Physics Research Section A-accelerators Spectrometers Detectors and Associated Equipment","volume":"1073 ","pages":"Article 170281"},"PeriodicalIF":1.5,"publicationDate":"2025-02-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143421640","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
N. Grundmanis , A. Sarakovskis , A. Lupilov , V. Gostilo , A. Owens , K. Pudzs
{"title":"The X- and gamma-ray detection properties of CsPbBr3 perovskite crystals grown by the Bridgman–Stockbarger method","authors":"N. Grundmanis , A. Sarakovskis , A. Lupilov , V. Gostilo , A. Owens , K. Pudzs","doi":"10.1016/j.nima.2025.170305","DOIUrl":"10.1016/j.nima.2025.170305","url":null,"abstract":"<div><div>In this paper we present the results of measurements on CsPbBr<sub>3</sub> perovskite crystals grown by the Bridgman-Stockbarger method which have shown promise as X- and gamma-ray detection media. The crystal structure, trap concentration (3.45 × 10<sup>10</sup> cm<sup>−3</sup>), specific resistivity (1.5 × 10<sup>9</sup> Ω cm) and other electrophysical characteristics which determine the spectrometric performance were examined. The X- and gamma-ray performance of planar, hemispherical and ring test detectors based on CsPbBr<sub>3</sub> crystals of dimensions of 5.0 × 5.0 × 3.0 mm<sup>3</sup> were evaluated. The energy resolution of the detector with ring electrodes measured using standard <sup>241</sup>Am, <sup>57</sup>Co and <sup>137</sup>Cs and <sup>60</sup>Co radioactive sources was: 2.3 keV (16%) at 14.0 keV; 2.7 keV (4.5%) at 59.5 keV; 12.0 keV (1.8%) at 662 keV and 18.6 keV (1.4%) at 1332 keV. The measured hole mobility-lifetime products (μτ) were as high as 3 × 10<sup>−3</sup> cm<sup>2</sup>/V.</div></div>","PeriodicalId":19359,"journal":{"name":"Nuclear Instruments & Methods in Physics Research Section A-accelerators Spectrometers Detectors and Associated Equipment","volume":"1073 ","pages":"Article 170305"},"PeriodicalIF":1.5,"publicationDate":"2025-02-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143421642","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
S. Bähr , H. Bae , J. Becker , M. Bertemes , M. Campajola , T. Ferber , T. Forsthofer , S. Hiesl , G. Inguglia , Y. Iwasaki , T. Jülg , C. Kiesling , A.C. Knoll , T. Koga , Y.-T. Lai , A. Lenz , Y. Liu , F. Meggendorfer , H. Nakazawa , M. Neu , J. Yin
{"title":"The neural network first-level hardware track trigger of the Belle II experiment","authors":"S. Bähr , H. Bae , J. Becker , M. Bertemes , M. Campajola , T. Ferber , T. Forsthofer , S. Hiesl , G. Inguglia , Y. Iwasaki , T. Jülg , C. Kiesling , A.C. Knoll , T. Koga , Y.-T. Lai , A. Lenz , Y. Liu , F. Meggendorfer , H. Nakazawa , M. Neu , J. Yin","doi":"10.1016/j.nima.2025.170279","DOIUrl":"10.1016/j.nima.2025.170279","url":null,"abstract":"<div><div>We describe the principles and performance of the first-level (“L1”) hardware track trigger of Belle II<!--> <!-->, which uses the information of Belle II<!--> <!-->’s Central Drift Chamber (“CDC”) and provides three-dimensional track candidates based on neural networks. The inputs to the networks are “2D” track candidates in the plane transverse to the electron–positron beams, obtained via Hough transforms, and selected information from the stereo layers of the CDC. The networks then provide estimates for the origin of the track candidates in direction of the colliding beams (“<span><math><mi>z</mi></math></span>-vertex”), as well as their polar emission angles <span><math><mi>θ</mi></math></span>. Using a suitable cut <span><math><mi>d</mi></math></span> on the <span><math><mi>z</mi></math></span>-vertices of the “neural” tracks allows us to identify events coming from the collision region (<span><math><mrow><mi>z</mi><mo>≈</mo><mn>0</mn></mrow></math></span>), and to suppress the overwhelming background from outside. Requiring <span><math><mrow><mrow><mo>|</mo><mi>z</mi><mo>|</mo></mrow><mo><</mo><mi>d</mi></mrow></math></span> for at least one neural track in an event with two or more 2D candidates will set an L1 track trigger. The networks also enable a minimum bias trigger, requiring a single 2D track candidate validated by a neural track with a momentum larger than 0.7 GeV in addition to the <span><math><mrow><mo>|</mo><mi>z</mi><mo>|</mo></mrow></math></span> condition. We also sketch our concepts for upgrading the neural trigger in view of rising instantaneous luminosities, accompanied by increasing backgrounds.</div></div>","PeriodicalId":19359,"journal":{"name":"Nuclear Instruments & Methods in Physics Research Section A-accelerators Spectrometers Detectors and Associated Equipment","volume":"1073 ","pages":"Article 170279"},"PeriodicalIF":1.5,"publicationDate":"2025-02-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143378864","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}