Pub Date : 2024-05-01DOI: 10.1088/1748-0221/19/05/t05018
A. Saraswat, R. Bhattacharyay, S. Gedupudi, P. Chaudhuri
Molten lead (Pb) and its alloys (PbBi and PbLi) are of immense interest for various nuclear engineering applications, including but not limited to advanced Lead-cooled Fast Reactors (LFRs), tritium Breeding Blankets (BBs) of fusion power plants and spallation targets for Accelerator-Driven Systems (ADS). Owing to their attractive thermophysical properties, these advanced fluids assert their candidacy to address the critical requirements of neutron multiplication, neutron moderation, high temperature coolants and tritium breeders, enabling the operation of next generation nuclear systems at high temperatures with better efficiencies. However, for numerous reasons such as a compromise of structural integrity at the heat transfer interface, presence of an inert cover gas during charging of molten metal in the loop, and the fusion fuel cycle itself may lead to molten metal-gas two-phase flows with high density ratios. At present, no effective diagnostics exist to detect such operational and accidental occurrences in high temperature molten metal systems resulting in a severe lack of relevant experimental studies. To address these limitations and to advance the current understanding toward two-phase regimes in high temperature Pb-based melts, the present work focuses on the design and assembly aspects of an electrical conductivity-based two-phase detection sensor array, utilizing high purity α-Al2O4 coatings with AlPO4 binder as electrical insulation layers. This paper discusses the design considerations, thermal analysis, systematic selection of structural/functional components along with preliminary results from the probe performance tests in very high temperature (600°C) static molten Pb column for real time detection of argon gas bubbles rising within the melt. Quantitative estimations of time-averaged void fraction, average bubble impaction frequency and average bubble residence time are presented from the preliminary experimental investigations.
{"title":"Design, fabrication and validation of an electrical conductivity principle based two-phase detection sensor array for molten lead (Pb) based heavy metal coolants up to 600^∘C","authors":"A. Saraswat, R. Bhattacharyay, S. Gedupudi, P. Chaudhuri","doi":"10.1088/1748-0221/19/05/t05018","DOIUrl":"https://doi.org/10.1088/1748-0221/19/05/t05018","url":null,"abstract":"\u0000 Molten lead (Pb) and its alloys (PbBi and PbLi) are of\u0000 immense interest for various nuclear engineering applications,\u0000 including but not limited to advanced Lead-cooled Fast Reactors\u0000 (LFRs), tritium Breeding Blankets (BBs) of fusion power plants and\u0000 spallation targets for Accelerator-Driven Systems (ADS). Owing to\u0000 their attractive thermophysical properties, these advanced fluids\u0000 assert their candidacy to address the critical requirements of\u0000 neutron multiplication, neutron moderation, high temperature\u0000 coolants and tritium breeders, enabling the operation of next\u0000 generation nuclear systems at high temperatures with better\u0000 efficiencies. However, for numerous reasons such as a compromise of\u0000 structural integrity at the heat transfer interface, presence of an\u0000 inert cover gas during charging of molten metal in the loop, and the\u0000 fusion fuel cycle itself may lead to molten metal-gas two-phase\u0000 flows with high density ratios. At present, no effective diagnostics\u0000 exist to detect such operational and accidental occurrences in high\u0000 temperature molten metal systems resulting in a severe lack of\u0000 relevant experimental studies. To address these limitations and to\u0000 advance the current understanding toward two-phase regimes in high\u0000 temperature Pb-based melts, the present work focuses on the design\u0000 and assembly aspects of an electrical conductivity-based two-phase\u0000 detection sensor array, utilizing high purity\u0000 α-Al2O4 coatings with AlPO4 binder as\u0000 electrical insulation layers. This paper discusses the design\u0000 considerations, thermal analysis, systematic selection of\u0000 structural/functional components along with preliminary results from\u0000 the probe performance tests in very high temperature\u0000 (600°C) static molten Pb column for real time detection of\u0000 argon gas bubbles rising within the melt. Quantitative estimations\u0000 of time-averaged void fraction, average bubble impaction frequency\u0000 and average bubble residence time are presented from the preliminary\u0000 experimental investigations.","PeriodicalId":16184,"journal":{"name":"Journal of Instrumentation","volume":null,"pages":null},"PeriodicalIF":1.3,"publicationDate":"2024-05-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141142005","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2024-05-01DOI: 10.1088/1748-0221/19/05/p05063
G. Aad, B. Abbott, D. Abbott, J. Abdallah, K. Abeling, S. Abidi, A. Aboulhorma, S. Abovyan, H. Abramowicz, H. Abreu, Y. Abulaiti, A. Abusleme Hoffman, B. Acharya, C. Adam Bourdarios, L. Adamczyk, L. Adamek, S. Addepalli, J. Adelman, M. Adersberger, A. Adiguzel, S. Adorni, T. Adye, A. Affolder, Y. Afik, M. N. Agaras, J. Agarwala, A. Aggarwal, C. Agheorghiesei, J. A. Aguilar-Saavedra, A. Ahmad, F. Ahmadov, W. S. Ahmed, S. Ahuja, X. Ai, G. Aielli, M. Ait Tamlihat, B. Aitbenchikh, I. Aizenberg, M. Akbiyik, T. Åkesson, G. Akhperjanyan, A. V. Akimov, K. Al Khoury, G. Alberghi, J. Albert, P. Albicocco, S. Alderweireldt, M. Aleksa, I. Aleksandrov, C. Alexa, T. Alexopoulos, A. Alfonsi, F. Alfonsi, M. Alhroob, B. Ali, S. Ali, M. Aliev, G. Alimonti, W. Alkakhi, C. Allaire, J. Allard, B. Allbrooke, C. Allendes Flores, P. Allport, A. Aloisio, F. Alonso, C. Alpigiani, M. Alvarez Estevez, B. Álvarez González, M. Alviggi, M. Aly, Y. Amaral Coutinho, A. Ambler, C. Amelung, M. Amerl, C. Ames, D. Amidei, S. Amor Dos Santos,
The ATLAS detector is installed in its experimental cavern at Point 1 of the CERN Large Hadron Collider. During Run 2 of the LHC, a luminosity of ℒ = 2 × 1034 cm-2 s-1 was routinely achieved at the start of fills, twice the design luminosity. For Run 3, accelerator improvements, notably luminosity levelling, allow sustained running at an instantaneous luminosity of ℒ = 2 × 1034 cm-2 s-1, with an average of up to 60 interactions per bunch crossing. The ATLAS detector has been upgraded to recover Run 1 single-lepton trigger thresholds while operating comfortably under Run 3 sustained pileup conditions. A fourth pixel layer 3.3 cm from the beam axis was added before Run 2 to improve vertex reconstruction and b-tagging performance. New Liquid Argon Calorimeter digital trigger electronics, with corresponding upgrades to the Trigger and Data Acquisition system, take advantage of a factor of 10 finer granularity to improve triggering on electrons, photons, taus, and hadronic signatures through increased pileup rejection. The inner muon endcap wheels were replaced by New Small Wheels with Micromegas and small-strip Thin Gap Chamber detectors, providing both precision tracking and Level-1 Muon trigger functionality. Trigger coverage of the inner barrel muon layer near one endcap region was augmented with modules integrating new thin-gap resistive plate chambers and smaller-diameter drift-tube chambers. Tile Calorimeter scintillation counters were added to improve electron energy resolution and background rejection. Upgrades to Minimum Bias Trigger Scintillators and Forward Detectors improve luminosity monitoring and enable total proton-proton cross section, diffractive physics, and heavy ion measurements. These upgrades are all compatible with operation in the much harsher environment anticipated after the High-Luminosity upgrade of the LHC and are the first steps towards preparing ATLAS for the High-Luminosity upgrade of the LHC. This paper describes the Run 3 configuration of the ATLAS detector.
{"title":"The ATLAS experiment at the CERN Large Hadron Collider: a description of the detector configuration for Run 3","authors":"G. Aad, B. Abbott, D. Abbott, J. Abdallah, K. Abeling, S. Abidi, A. Aboulhorma, S. Abovyan, H. Abramowicz, H. Abreu, Y. Abulaiti, A. Abusleme Hoffman, B. Acharya, C. Adam Bourdarios, L. Adamczyk, L. Adamek, S. Addepalli, J. Adelman, M. Adersberger, A. Adiguzel, S. Adorni, T. Adye, A. Affolder, Y. Afik, M. N. Agaras, J. Agarwala, A. Aggarwal, C. Agheorghiesei, J. A. Aguilar-Saavedra, A. Ahmad, F. Ahmadov, W. S. Ahmed, S. Ahuja, X. Ai, G. Aielli, M. Ait Tamlihat, B. Aitbenchikh, I. Aizenberg, M. Akbiyik, T. Åkesson, G. Akhperjanyan, A. V. Akimov, K. Al Khoury, G. Alberghi, J. Albert, P. Albicocco, S. Alderweireldt, M. Aleksa, I. Aleksandrov, C. Alexa, T. Alexopoulos, A. Alfonsi, F. Alfonsi, M. Alhroob, B. Ali, S. Ali, M. Aliev, G. Alimonti, W. Alkakhi, C. Allaire, J. Allard, B. Allbrooke, C. Allendes Flores, P. Allport, A. Aloisio, F. Alonso, C. Alpigiani, M. Alvarez Estevez, B. Álvarez González, M. Alviggi, M. Aly, Y. Amaral Coutinho, A. Ambler, C. Amelung, M. Amerl, C. Ames, D. Amidei, S. Amor Dos Santos,","doi":"10.1088/1748-0221/19/05/p05063","DOIUrl":"https://doi.org/10.1088/1748-0221/19/05/p05063","url":null,"abstract":"\u0000 The ATLAS detector is installed in its experimental cavern\u0000 at Point 1 of the CERN Large Hadron Collider. During Run 2 of the\u0000 LHC, a luminosity of\u0000 ℒ = 2 × 1034 cm-2 s-1 was\u0000 routinely achieved at the start of fills, twice the design\u0000 luminosity. For Run 3, accelerator improvements, notably luminosity\u0000 levelling, allow sustained running at an instantaneous luminosity of\u0000 ℒ = 2 × 1034 cm-2 s-1,\u0000 with an average of up to 60 interactions per bunch crossing. The\u0000 ATLAS detector has been upgraded to recover Run 1 single-lepton\u0000 trigger thresholds while operating comfortably under Run 3 sustained\u0000 pileup conditions. A fourth pixel layer 3.3 cm from the beam axis\u0000 was added before Run 2 to improve vertex reconstruction and\u0000 b-tagging performance. New Liquid Argon Calorimeter digital\u0000 trigger electronics, with corresponding upgrades to the Trigger and\u0000 Data Acquisition system, take advantage of a factor of 10 finer\u0000 granularity to improve triggering on electrons, photons, taus, and\u0000 hadronic signatures through increased pileup rejection. The inner\u0000 muon endcap wheels were replaced by New Small Wheels with Micromegas\u0000 and small-strip Thin Gap Chamber detectors, providing both precision\u0000 tracking and Level-1 Muon trigger functionality. Trigger coverage of\u0000 the inner barrel muon layer near one endcap region was augmented\u0000 with modules integrating new thin-gap resistive plate chambers and\u0000 smaller-diameter drift-tube chambers. Tile Calorimeter scintillation\u0000 counters were added to improve electron energy resolution and\u0000 background rejection. Upgrades to Minimum Bias Trigger Scintillators\u0000 and Forward Detectors improve luminosity monitoring and enable total\u0000 proton-proton cross section, diffractive physics, and heavy ion\u0000 measurements. These upgrades are all compatible with operation in\u0000 the much harsher environment anticipated after the High-Luminosity\u0000 upgrade of the LHC and are the first steps towards preparing ATLAS\u0000 for the High-Luminosity upgrade of the LHC. This paper describes\u0000 the Run 3 configuration of the ATLAS detector.","PeriodicalId":16184,"journal":{"name":"Journal of Instrumentation","volume":null,"pages":null},"PeriodicalIF":1.3,"publicationDate":"2024-05-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141141427","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2024-05-01DOI: 10.1088/1748-0221/19/05/c05033
W. Bontems, D. Dzahini
The paper describes a new figure of merit reachable in terms of very low power dissipation for a 12 bit, 40 MS/s Analog to Digital Converter in a 65 nm CMOS process with 1 V power supply. A differential time interleaved successive approximations register architecture is used. Each individual ADC channel is optimized with regard to power consumption hence interleaving 28 ADC channels in an analog memory like method, the total power consumption is only 280 μW including all the reference voltage drivers, the clock management and the digital sections. The total layout area of this converter is 0.87 mm2.
{"title":"Design of a very low power 12 bits, 40 MS/s ADC based on a time-interleaved SAR architecture","authors":"W. Bontems, D. Dzahini","doi":"10.1088/1748-0221/19/05/c05033","DOIUrl":"https://doi.org/10.1088/1748-0221/19/05/c05033","url":null,"abstract":"\u0000 The paper describes a new figure of merit reachable in terms of very low power dissipation for a 12 bit, 40 MS/s Analog to Digital Converter in a 65 nm CMOS process with 1 V power supply. A differential time interleaved successive approximations register architecture is used. Each individual ADC channel is optimized with regard to power consumption hence interleaving 28 ADC channels in an analog memory like method, the total power consumption is only 280 μW including all the reference voltage drivers, the clock management and the digital sections. The total layout area of this converter is 0.87 mm2.","PeriodicalId":16184,"journal":{"name":"Journal of Instrumentation","volume":null,"pages":null},"PeriodicalIF":1.3,"publicationDate":"2024-05-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141047358","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2024-05-01DOI: 10.1088/1748-0221/19/05/p05017
L.S. Jones, C. Crews, J. Ivory, A. Holland
Evaluation of detectors for a soft X-ray imaging spectrometer has resulted in the need to understand the effect of charge spreading on apparent detector noise properties, and therefore achievable energy resolution. This paper presents a mathematical model for the processes leading to increased uncertainty within a simplified X-ray reconstruction process. This is a description for additional uncertainty introduced by the process of collecting X-ray generated electrons into a region of noisy pixels and reconstructing the recorded pixels values back into an estimated X-ray energy value. The predictions of the model, and preliminary experimental verification are shown.
对软 X 射线成像光谱仪的探测器进行评估，需要了解电荷扩散对探测器表观噪声特性的影响，从而了解可实现的能量分辨率。本文针对导致简化 X 射线重建过程中不确定性增加的过程提出了一个数学模型。该模型描述了将 X 射线产生的电子收集到噪声像素区域，并将记录的像素值重建为估计的 X 射线能量值的过程中引入的额外不确定性。图中显示了模型的预测结果和初步的实验验证。
{"title":"A model for photon counting X-ray event reconstruction uncertainty","authors":"L.S. Jones, C. Crews, J. Ivory, A. Holland","doi":"10.1088/1748-0221/19/05/p05017","DOIUrl":"https://doi.org/10.1088/1748-0221/19/05/p05017","url":null,"abstract":"\u0000 Evaluation of detectors for a soft X-ray imaging\u0000 spectrometer has resulted in the need to understand the effect of\u0000 charge spreading on apparent detector noise properties, and\u0000 therefore achievable energy resolution. This paper presents a\u0000 mathematical model for the processes leading to increased\u0000 uncertainty within a simplified X-ray reconstruction process. This\u0000 is a description for additional uncertainty introduced by the\u0000 process of collecting X-ray generated electrons into a region of\u0000 noisy pixels and reconstructing the recorded pixels values back into\u0000 an estimated X-ray energy value. The predictions of the model, and\u0000 preliminary experimental verification are shown.","PeriodicalId":16184,"journal":{"name":"Journal of Instrumentation","volume":null,"pages":null},"PeriodicalIF":1.3,"publicationDate":"2024-05-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141050140","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2024-05-01DOI: 10.1088/1748-0221/19/05/t05012
J. Nsor, T. Ansah-Narh, E. Proven-Adzri, J. Koranteng-Acquah, E.K. Mornoh
Ghana's 32-meter radio telescope, inaugurated in August 2017, was once a redundant telecommunications dish that underwent conversion. Prior to this transformation, feasibility studies were conducted to assess the dish's structural integrity, technical compatibility, and economic viability. These studies aimed to determine if the conversion project could be technically achieved given the available technology, expertise, and resources. This paper delves into the engineering considerations surrounding structural, mechanical, software, control and monitoring, radio frequency, and timing frequency reference requirements that distinguish the operation of a radio telescope from its former role as a satellite earth station. Significant components such as the azimuth bearing, sub-reflector support, cable wrap, and electrical motors underwent replacement. Additionally, a new C-band receiver, radio frequency controller, active hydrogen maser timing frequency, and software were developed. Testing protocols to meet science requirements for both single-dish observations and Very Long Baseline Interferometry (VLBI) are also discussed. The conversion process proved to be lengthy and encountered numerous unforeseen circumstances, yet it provided invaluable learning experiences for a developing country like Ghana.
{"title":"The engineering face-lift of the 32m dish: technical upgrades of Ghana Radio Astronomy Observatory (GRAO)","authors":"J. Nsor, T. Ansah-Narh, E. Proven-Adzri, J. Koranteng-Acquah, E.K. Mornoh","doi":"10.1088/1748-0221/19/05/t05012","DOIUrl":"https://doi.org/10.1088/1748-0221/19/05/t05012","url":null,"abstract":"\u0000 Ghana's 32-meter radio telescope, inaugurated in August 2017, was once a redundant\u0000 telecommunications dish that underwent conversion. Prior to this transformation, feasibility\u0000 studies were conducted to assess the dish's structural integrity, technical compatibility, and\u0000 economic viability. These studies aimed to determine if the conversion project could be\u0000 technically achieved given the available technology, expertise, and resources. This paper delves\u0000 into the engineering considerations surrounding structural, mechanical, software, control and\u0000 monitoring, radio frequency, and timing frequency reference requirements that distinguish the\u0000 operation of a radio telescope from its former role as a satellite earth station. Significant\u0000 components such as the azimuth bearing, sub-reflector support, cable wrap, and electrical motors\u0000 underwent replacement. Additionally, a new C-band receiver, radio frequency controller, active\u0000 hydrogen maser timing frequency, and software were developed. Testing protocols to meet science\u0000 requirements for both single-dish observations and Very Long Baseline Interferometry (VLBI) are\u0000 also discussed. The conversion process proved to be lengthy and encountered numerous unforeseen\u0000 circumstances, yet it provided invaluable learning experiences for a developing country\u0000 like Ghana.","PeriodicalId":16184,"journal":{"name":"Journal of Instrumentation","volume":null,"pages":null},"PeriodicalIF":1.3,"publicationDate":"2024-05-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141041752","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2024-05-01DOI: 10.1088/1748-0221/19/05/p05020
Bangping Xiong, Bo Wan, Yang Zhao, Daibo Yang, Xi Ge, Shangqing Sun
The fiber-optic neutron detector consists principally of a neutron-sensitive scintillator, optical fiber, and photomultiplier tube. It has features such as small size, real-time online measurement capability, and high resistance to electromagnetic interference. This detector is excellent for neutron detection in areas with limited space and strong electromagnetic interference. However, its small size results in a comparatively low neutron sensitivity. The goal of this study is to look into the relationship between detector parameters and performance in order to improve the detector design. The research begins with the development of a detector model using Monte Carlo simulation programs to investigate the relationship between the 6LiF/ZnO:Ga mass ratio, thickness, wavelength-shifting fiber length, and detector performance. The 6LiF/ZnO:Ga mass ratio was then used as the test parameter to create equivalent detector samples for experimental validation. The results show that the detector has the highest neutron sensitivity when the mass ratio of 6LiF/ZnO:Ga is 1:1. This pattern is consistent with theoretical simulation results, indicating that the optimization strategy for detector parameters is feasible. The results of this work give a theoretical foundation for the development and practical implementation of the fiber-optic neutron detector.
{"title":"An optimization design for fiber-optic neutron detector based on 6LiF/ZnO:Ga and wavelength shifting fibers","authors":"Bangping Xiong, Bo Wan, Yang Zhao, Daibo Yang, Xi Ge, Shangqing Sun","doi":"10.1088/1748-0221/19/05/p05020","DOIUrl":"https://doi.org/10.1088/1748-0221/19/05/p05020","url":null,"abstract":"\u0000 The fiber-optic neutron detector consists principally of a\u0000 neutron-sensitive scintillator, optical fiber, and photomultiplier\u0000 tube. It has features such as small size, real-time online\u0000 measurement capability, and high resistance to electromagnetic\u0000 interference. This detector is excellent for neutron detection in\u0000 areas with limited space and strong electromagnetic\u0000 interference. However, its small size results in a comparatively low\u0000 neutron sensitivity. The goal of this study is to look into the\u0000 relationship between detector parameters and performance in order to\u0000 improve the detector design. The research begins with the\u0000 development of a detector model using Monte Carlo simulation\u0000 programs to investigate the relationship between the\u0000 6LiF/ZnO:Ga mass ratio, thickness, wavelength-shifting fiber\u0000 length, and detector performance. The 6LiF/ZnO:Ga mass ratio\u0000 was then used as the test parameter to create equivalent detector\u0000 samples for experimental validation. The results show that the\u0000 detector has the highest neutron sensitivity when the mass ratio of\u0000 6LiF/ZnO:Ga is 1:1. This pattern is consistent with\u0000 theoretical simulation results, indicating that the optimization\u0000 strategy for detector parameters is feasible. The results of this\u0000 work give a theoretical foundation for the development and practical\u0000 implementation of the fiber-optic neutron detector.","PeriodicalId":16184,"journal":{"name":"Journal of Instrumentation","volume":null,"pages":null},"PeriodicalIF":1.3,"publicationDate":"2024-05-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141054443","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2024-05-01DOI: 10.1088/1748-0221/19/05/c05021
H. Khachatryan, L. Grigoryan, V. Kotanjyan, M. Grigoryan, H.P. Harutyunyan, J. Markosyan, G.V. Margaryan, A. Saharian
We investigate the quasi-coherent radiation from a train of electron bunches moving along the axis of a cylindrical waveguide, assuming that a part of the waveguide is filled with a dielectric medium. For the permittivity of the latter, the general case of dispersion is considered. It is shown that under certain conditions on the permittivity of the medium and on the values of the problem parameters, the waveguide modes become equidistant. As a consequence, quasi-coherent Cherenkov radiation from the train of bunches may be generated on the first several waveguide modes simultaneously. An example of dispersion law is provided for which the corresponding Cherenkov radiation is suppressed.
{"title":"Quasi-coherent radiation from a train of electron bunches inside a waveguide partially filled with dielectric","authors":"H. Khachatryan, L. Grigoryan, V. Kotanjyan, M. Grigoryan, H.P. Harutyunyan, J. Markosyan, G.V. Margaryan, A. Saharian","doi":"10.1088/1748-0221/19/05/c05021","DOIUrl":"https://doi.org/10.1088/1748-0221/19/05/c05021","url":null,"abstract":"\u0000 We investigate the quasi-coherent radiation from a train of electron bunches moving along the axis of a cylindrical waveguide, assuming that a part of the waveguide is filled with a dielectric medium. For the permittivity of the latter, the general case of dispersion is considered. It is shown that under certain conditions on the permittivity of the medium and on the values of the problem parameters, the waveguide modes become equidistant. As a consequence, quasi-coherent Cherenkov radiation from the train of bunches may be generated on the first several waveguide modes simultaneously. An example of dispersion law is provided for which the corresponding Cherenkov radiation is suppressed.","PeriodicalId":16184,"journal":{"name":"Journal of Instrumentation","volume":null,"pages":null},"PeriodicalIF":1.3,"publicationDate":"2024-05-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141036529","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
The implementation of Slicon Photon-Multipliers (SiPMs) wave-length shifting (WLS) fibers light response system in liquid argon (LAr) is a promising technology for suppressing background in rare event experiments. Moreover, it is particularly relevant for experiments that utilize high-purity germanium (HPGe) detectors directly operated in LAr, such as the direct detection of dark matter and neutrinoless double beta decay. In this work, we exhibit a designed WLS fiber for the LAr detector, verify the feasibility of the manufacturing technology, and simulation research about its light collection performance. The novel fiber incorporates two materials, styrene and 1,1,4,4-tetraphenyl-1,3-butadiene (TPB). The pre-experiments proved that the fiber has good WLS and light-conducting properties for ultraviolet light. In addition, the effect of different light collection methods on detection efficiency was assessed by Geant4 simulation. Our results show that adding optical fibers can significantly increase light collection efficiency. Compared with the design of TPB coating with commercial fiber, the new structure of WLS fiber can improve the light collection efficiency by 50%. The simulation results indicate that the new fiber structure can enhance the light collection efficiency of the LAr detection system, thereby improving the anti-coincidence system's performance in rare event experiments.
在液态氩（LAr）中实施Slicon光子倍增器（SiPMs）波长偏移（WLS）光纤光响应系统是抑制罕见事件实验背景的一项很有前途的技术。此外，它对于利用直接在 LAr 中运行的高纯锗（HPGe）探测器的实验尤其重要，例如暗物质和无中子双贝塔衰变的直接探测。在这项工作中，我们展示了为 LAr 探测器设计的 WLS 光纤，验证了制造技术的可行性，并对其集光性能进行了模拟研究。这种新型光纤采用了苯乙烯和 1,1,4,4-四苯基-1,3-丁二烯（TPB）两种材料。前期实验证明，该纤维具有良好的 WLS 性能和紫外线导光性能。此外，我们还通过 Geant4 仿真评估了不同集光方式对检测效率的影响。结果表明，添加光纤可显著提高光收集效率。与使用商用光纤的 TPB 涂层设计相比，WLS 光纤的新结构可将光收集效率提高 50%。仿真结果表明，新的光纤结构可以提高 LAr 检测系统的光收集效率，从而改善反巧合系统在罕见事件实验中的性能。
{"title":"Design of high-light-collection-efficiency optical fiber for germanium detectors immersed in liquid argon","authors":"Yulu Yan, Lei Zhang, Yu Liu, Shin-Ted Lin, Jingjun Zhu, Shu-Kui Liu, Changhao Fang, Changjian Tang, Haoyang Xing","doi":"10.1088/1748-0221/19/05/p05026","DOIUrl":"https://doi.org/10.1088/1748-0221/19/05/p05026","url":null,"abstract":"\u0000 The implementation of Slicon Photon-Multipliers (SiPMs) wave-length shifting (WLS) fibers light response system in liquid argon (LAr) is a promising technology for suppressing background in rare event experiments. Moreover, it is particularly relevant for experiments that utilize high-purity germanium (HPGe) detectors directly operated in LAr, such as the direct detection of dark matter and neutrinoless double beta decay. In this work, we exhibit a designed WLS fiber for the LAr detector, verify the feasibility of the manufacturing technology, and simulation research about its light collection performance. The novel fiber incorporates two materials, styrene and 1,1,4,4-tetraphenyl-1,3-butadiene (TPB). The pre-experiments proved that the fiber has good WLS and light-conducting properties for ultraviolet light. In addition, the effect of different light collection methods on detection efficiency was assessed by Geant4 simulation. Our results show that adding optical fibers can significantly increase light collection efficiency. Compared with the design of TPB coating with commercial fiber, the new structure of WLS fiber can improve the light collection efficiency by 50%. The simulation results indicate that the new fiber structure can enhance the light collection efficiency of the LAr detection system, thereby improving the anti-coincidence system's performance in rare event experiments.","PeriodicalId":16184,"journal":{"name":"Journal of Instrumentation","volume":null,"pages":null},"PeriodicalIF":1.3,"publicationDate":"2024-05-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141044399","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2024-05-01DOI: 10.1088/1748-0221/19/05/p05014
Yingfeng Xu, Shitao Wang
A novel approach has been proposed to effectively separate cascaded and closely packed full energy peaks in the energy spectrum of γ detector arrays. By conducting a sequence of γ-γ coincidence analyses on the energy spectrum, it is feasible to obtain a spectrum that represents the product of these packed peaks. We have designated the newly obtained spectrum as the “product spectrum”. The energy spectrum and the newly obtained product spectrum can be simultaneously fitted, enabling a more precise fitting and separation of the closely packed peaks. This method has been mathematically proven, and validated through the use of Monte Carlo simulation. The systematic errors of this method are also taken into consideration.
{"title":"A novel approach for disentangling packed peaks in the energy spectrum of γ detector arrays through γ-γ coincidence analysis","authors":"Yingfeng Xu, Shitao Wang","doi":"10.1088/1748-0221/19/05/p05014","DOIUrl":"https://doi.org/10.1088/1748-0221/19/05/p05014","url":null,"abstract":"\u0000 A novel approach has been proposed to effectively separate cascaded and closely packed full energy peaks in the energy spectrum of γ detector arrays. By conducting a sequence of γ-γ coincidence analyses on the energy spectrum, it is feasible to obtain a spectrum that represents the product of these packed peaks. We have designated the newly obtained spectrum as the “product spectrum”. The energy spectrum and the newly obtained product spectrum can be simultaneously fitted, enabling a more precise fitting and separation of the closely packed peaks. This method has been mathematically proven, and validated through the use of Monte Carlo simulation. The systematic errors of this method are also taken into consideration.","PeriodicalId":16184,"journal":{"name":"Journal of Instrumentation","volume":null,"pages":null},"PeriodicalIF":1.3,"publicationDate":"2024-05-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141053251","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2024-05-01DOI: 10.1088/1748-0221/19/05/p05033
H.P. Li, H.Q. Su, G. Kong, W. L. Pan, J.R.L. Lin, Y.R. Lu, S. Wang
The coupled structure with ladder radio-frequency quadrupole (RFQ) and interdigital H-type drift tube linac (IH DTL) has been proposed to accelerate the proton beam to several MeV with high acceleration gradient and one RF feed-in system. A ladder RFQ-IH DTL coupled structure was designed to accelerate a proton beam 2.5 MeV with a peak current of 15 mA. Detailed dynamics optimization and error study were performed to achieve high transmission efficiency and small emittance growth, including ladder RFQ, coupling section and IH DTL section. The Kombinierte Null Grad Struktur (KONUS) dynamics scheme with two quadrupole doublets (QDs) was adopted in the IH-DTL section. Start-to-end beam tracking results showed that the proton beam can be accelerated to the final energy with a length of 2.11 m and a transmission efficiency above 98.5%. In addition, we performed error sensitivity analysis and the combined error study to evaluate the error tolerance limits of the ladder RFQ-IH DTL coupled structure.
我们提出了梯形射频四极杆（RFQ）和数字间 H 型漂移管直列加速器（IH DTL）耦合结构，以高加速梯度和一个射频馈入系统将质子束加速到几 MeV。设计的梯形 RFQ-IH DTL 耦合结构可将质子束加速到 2.5 MeV，峰值电流为 15 mA。为了实现高传输效率和小发射增长，对梯形 RFQ、耦合部分和 IH DTL 部分进行了详细的动力学优化和误差研究。IH-DTL 部分采用了带有两个四极双极（QD）的 Kombinierte Null Grad Struktur（KONUS）动力学方案。开始到结束的束流跟踪结果表明，质子束可以加速到最终能量，长度为 2.11 米，传输效率超过 98.5%。此外，我们还进行了误差敏感性分析和组合误差研究，以评估梯形 RFQ-IH DTL 耦合结构的误差容限。
{"title":"Beam dynamics design and error study of the coupled structure with ladder RFQ and IH-DTL","authors":"H.P. Li, H.Q. Su, G. Kong, W. L. Pan, J.R.L. Lin, Y.R. Lu, S. Wang","doi":"10.1088/1748-0221/19/05/p05033","DOIUrl":"https://doi.org/10.1088/1748-0221/19/05/p05033","url":null,"abstract":"\u0000 The coupled structure with ladder radio-frequency quadrupole\u0000 (RFQ) and interdigital H-type drift tube linac (IH DTL) has been\u0000 proposed to accelerate the proton beam to several MeV with high\u0000 acceleration gradient and one RF feed-in system. A ladder RFQ-IH DTL\u0000 coupled structure was designed to accelerate a proton beam 2.5 MeV\u0000 with a peak current of 15 mA. Detailed dynamics optimization and\u0000 error study were performed to achieve high transmission efficiency\u0000 and small emittance growth, including ladder RFQ, coupling section\u0000 and IH DTL section. The Kombinierte Null Grad Struktur (KONUS)\u0000 dynamics scheme with two quadrupole doublets (QDs) was adopted in\u0000 the IH-DTL section. Start-to-end beam tracking results showed that\u0000 the proton beam can be accelerated to the final energy with a length\u0000 of 2.11 m and a transmission efficiency above 98.5%. In addition,\u0000 we performed error sensitivity analysis and the combined error study\u0000 to evaluate the error tolerance limits of the ladder RFQ-IH DTL\u0000 coupled structure.","PeriodicalId":16184,"journal":{"name":"Journal of Instrumentation","volume":null,"pages":null},"PeriodicalIF":1.3,"publicationDate":"2024-05-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141056705","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
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