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light collection of the POLAR detector

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Science china(physics,Mechanics & Astronomy) 2010年第S1期53卷 43-46页

作者： dong yongwei,li yanguo,wu bobing,zhang yongjie & zhang shuangnan key laboratory of particle astrophysics,institute of high energy physics,chinese academy of sciences,beijing 100049,china key laboratory of particle astrophysics Institute of High Energy Physics Chinese Academy of Sciences Beijing China

POLAR is a compact polarimeter dedicated to measuring the polarization of GRBs between 50-350 *** light collection of 200 mm×6 mm×6 mm plastic bars has been simulated and optimized in order to get uniform response to X-rays at different points along one single *** to the Monte Carlo results,the amplitude uniformity strongly depends on the level of polishing of the scintillator surface and the covering.A uniformity of 89% is achieved with a prototype constructed by a non position-sensitive PMT and an array of 4×4 bars.

关键词： plastic scintillator light collection gamma-ray burst polarimeter

Temporal study of GRS 1915+105 with rms-flux relation:The importance of magnetic activities in the corona

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Science china(physics,Mechanics & Astronomy) 2010年第S1期53卷 120-124页

作者： HAN dong1,zhang shuangnan2 & SONG liMing2 1 Department of Engineering physics & Center for astrophysics,Tsinghua University,beijing 100084,china 2 key laboratory of particle astrophysics,institute of high energy physics,chinese academy of sciences,beijing 100049,china Department of Engineering physics & Center for astrophysics Tsinghua University Beijing China key laboratory of particle astrophysics Institute of High Energy Physics Chinese Academy of Sciences Beijing China

The rms-flux relations for some observations of GRS 1915+105 are *** rms-flux relations of the light curves in only one state,state C or state A,can be described by the simple non-linear model provided zhang;we thus interpret that such a linear relation reflects the relative importance of magnetic instability for X-ray emission in the corona of the system,compared to the thermal viscous instability for the X-ray emission in the accretion *** rms-flux relations for state B are very scattered,possibly because of the dominance of thermal viscous instability for the X-ray emission in the accretion *** complex rms-flux relations for the observations of transitions between two or three states are caused by the combination of the different rms-flux relations of these *** underlying physical processes are the combination of magnetic topology in the corona and thermal viscous instability in the accretion disk.

关键词： rms-flux relation data analysis GRS 1915+105 magnetic instability

Calibrating the HXMT collimators using diffuse illumination

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Science china(physics,Mechanics & Astronomy) 2010年第S1期53卷 36-39页

作者： HAN dong1,JIN yongjie1,wu Mei2 & zhang Zhi1 1 Department of Engineering physics & Center for astrophysics,Tsinghua University,beijing 100084,china 2 key laboratory of particle astrophysics,institute of high energy physics,chinese academy of sciences,beijing 100049,china Department of Engineering physics & Center for astrophysics Tsinghua University Beijing China key laboratory of particle astrophysics Institute of High Energy Physics Chinese Academy of Sciences Beijing China

We propose a new method to calibrate the HXMT collimators by measuring the optical point spread function(PSF) of the hard X-ray modulation telescope(HXMT).The light transmission of the collimator at different viewing angles with a camera and a diffuse backlight placed behind the collimator is *** method is much easier to accomplish than measuring the PSF with a parallel optical *** experimental results are very consistent with the *** PSF of the collimator of the high energy X-ray telescope on HXMT is found to be in good agreement with the design,with accuracy better than 1 arcmin.

关键词： HXMT collimator point spread function Monte Carlo simulation diffuse illumination

Experimental investigation of bed-to-wall heat transfer in fluidized beds of a Geldart B sorbent particle under a full spectrum of fluidization regime

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Particuology 2024年第10期93卷 235-246页

作者： Chenhuan Xu Yongmin zhang liang Wang Yiming zhang Tianlei Yang Feng Qiu Cenfan liu Shuai Jiang Ke dong State key laboratory of Heavy Oil Processing China University of PetroleumBeijing102249China beijing DERUNCHEN Environmental Protection Technology Co. LtdBeijing100022China key laboratory of Special Equipment Safety and energy-saving for State Market Regulation China Special Equipment Inspection and Research InstituteBeijing100029China

Fluidization technology has been used in CO_(2) capture processes, the successful design and operation of the heat exchangers involved in this process require much information on the bed-to-wall heat transfer of the sorbent particles in fluidized states. In this study, the bed-to-wall heat transfer coefficient (h) of a solid amine sorbent was measured by a heat transfer probe in a large-scale circulating fluidized bed cold model unit, where full spectrum of fluidization regimes can be realized. The corresponding hydrodynamic signals were also studied by pressure sensors and optical fiber probes to further explain the newly discovered phenomenon. The results show that in a dense bed, due to the counterbalanced effect of time fraction of packet and packet renewal frequency, h of the Geldart B particle reaches a peak within the bubbling fluidized regime, and the radial distribution of h are opposite in bubbling and turbulent fluidized regimes. In a fast fluidization regime, gas convection becomes the dominant factor affecting h when the solids holdup is low enough. Correlations were provided or recommended to guide the design of heat exchangers in the fluidized bed CO_(2) capture processes.

关键词： Bed-to-wall heattransfer Solid amine sorbent Geldart B particle Full spectrum of fluidization regime Correlation

Construction and performance test of charged particle detector array for MATE

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Nuclear Science and Techniques 2024年第8期35卷 92-100页

作者： Xiao‑Bin li Long‑Hui Ru Zhi‑Chao zhang Bing‑Feng Lv Ning‑Tao zhang Jin‑Long zhang Chen‑Gui Lu Bing‑Shui Gao Jun‑Bing Ma Fu‑Shuai Shi Satoru Terashima Xiao‑dong Xu Zhen Bai Shi‑Wei Xu Yan‑Yun Yang Hooi‑Jin Ong Xiao‑dong Tang institute of Modern physics(IMP) Chinese Academy of SciencesLanzhou 730000China School of Nuclear Science and Technology University of Chinese Academy of SciencesBeijing 100049China Research Center for Nuclear physics Osaka UniversityIbarakiOsaka 567‑0047Japan RIKEN Nishina Center WakoSaitama 351‑0198Japan Joint Department for Nuclear physics Lanzhou University and Institute of Modern PhysicsChinese Academy of SciencesLanzhou 730000China

A charged particle array named MATE-PA,which serves as an auxiliary detector system for a Multi-purpose Active-target Time projection chamber used in nuclear astrophysical and exotic beam Experiments(MATE),was *** array comprised of 20 single-sided strip-silicon detectors covering approximately 10%of the solid *** detectors facilitated the detection of reaction-induced charged particles that penetrate the active volume of the *** performance of MATE-PA has been experimentally studied using an alpha source and a 36-MeV 14 N beam injected into the MATE chamber on the radioactive ion beam line in Lanzhou(RIBLL).The chamber was filled with a gas mixture of 95%4 He and 5%CO_(2) at a pressure of 500 *** results indicated good separation of light-charged particles using the forward double-layer silicon detectors of *** energy resolution of the Si detectors was deduced to be approximately 1%(σ)for an energy loss of approximately 10 MeV caused by theα*** inclusion of MATE-PA improves particle identification and increases the dynamic range of the kinetic energy of charged particles,particularly that of theαparticles,up to approximately 15 MeV.

关键词： Silicon detector array Active target Time projection chamber

Stepped-up development of accelerator mass spectrometry method for the detection of ^(60)Fe with the HI-13 tandem accelerator

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Nuclear Science and Techniques 2024年第4期35卷 136-143页

作者： Yang zhang Sheng-Quan Yan Ming He Qing-zhang Zhao Wen-Hui zhang Chao-Xin Kan Jian-Ming Zhou Kang-Ning li Xiao-Fei Wang Jian-Cheng liu Zhao-Hua Peng Zhuo liang Ai-ling li Jian Zheng Qi-Wen Fan Yun-Ju li You-Bao Wang Zhi-Hong li Yang-Ping Shen Ding Nan Wei Nan Yu-Qiang zhang Jia-Ying-Hao li Jun-Wen Tian Jiang-lin Hou Chang-Xin Guo Zhi-Cheng zhang Ming-Hao Zhu Yu-Wen Chen Yu-Chen Jiang Tao Tian Jin-Long Ma Yi-Hui liu Jing-Yu dong Run-Long liu Mei-Yue-Nan Ma Yong-Shou Chen Wei-Ping liu Bing Guo china institute of Atomic energy P.O.Box 275(10)Beijing 102413China College of Science Southern University of Science and TechnologyShenzhen 518055China School of physics Xi’an Jiaotong UniversityXi’an 710049China

The Moon provides a unique environment for investigating nearby astrophysical events such as *** samples retain valuable information from these events,via detectable long-lived“fingerprint”radionuclides such as^(60)*** this work,we stepped up the development of an accelerator mass spectrometry(AMS)method for detecting^(60)Fe using the HI-13tandem accelerator at the china institute of Atomic energy(CIAE).Since interferences could not be sufficiently removed solely with the existing magnetic systems of the tandem accelerator and the following Q3D magnetic spectrograph,a Wien filter with a maximum voltage of±60 kV and a maximum magnetic field of 0.3 T was installed after the accelerator magnetic systems to lower the detection background for the low abundance nuclide^(60)Fe.A 1μm thick Si_(3)N_(4) foil was installed in front of the Q3D as an energy *** particle detection,a multi-anode gas ionization chamber was mounted at the center of the focal plane of the ***,an^(60)Fe sample with an abundance of 1.125×10^(-10)was used to test the new AMS *** results indicate that^(60)Fe can be clearly distinguished from the isobar^(60)*** sensitivity was assessed to be better than 4.3×10^(-14)based on blank sample measurements lasting 5.8 h,and the sensitivity could,in principle,be expected to be approximately 2.5×10^(-15)when the data were accumulated for 100 h,which is feasible for future lunar sample measurements because the main contaminants were sufficiently separated.

关键词： Accelerator mass spectrometry Wien filter Isobar separation Supernovae Chang'e-5 lunar samples

The high energy X-ray telescope (HE) onboard the Insight-HXMT astronomy satellite

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Science china(physics,Mechanics & Astronomy) 2020年第4期63卷 20-34页

作者： CongZhan liu YiFei zhang XuFang li XueFeng Lu Zhi Chang ZhengWei li AiMei zhang yongjie Jin HuiMing Yu Zhao zhang MinXue Fu YiBao Chen JianFeng Ji YuPeng Xu JingKang Deng RenCheng Shang GuoQing liu FangJun Lu shuangnan zhang yongwei dong TiPei li Mei wu yanguo li HuanYu Wang bobing wu yongjie zhang Zhi zhang Shaolin Xiong Yuan liu Shu zhang HongWei liu YiJung Yang Fan zhang key laboratory of particle astrophysics Institute of High Energy PhysicsChinese Academy of SciencesBeijing 100049China Department of Engineering physics Tsinghua UniversityBeijing 100084China Department of physics Tsinghua UniversityBeijing 100084China University of chinese academy of sciences Beijing 100049China

The Insight-Hard X-ray Modulation Telescope(Insight-HXMT) is a broadband X-ray and γ-ray(1-3000 ke V) astronomy satellite. One of its three main telescopes is the high energy X-ray telescope(HE). The main detector plane of HE comprises 18 Na I(Tl)/Cs I(Na) phoswich detectors, where Na I(Tl) is used as the primary detector to measure ~ 20-250 ke V photons incident from the field of view(FOV) defined by collimators, and Cs I(Na) is used as the active shielding detector to Na I(Tl) by pulse shape discrimination. Additionally, Cs I(Na) is used as an omnidirectional γ-ray monitor. The HE collimators have a diverse FOV,i.e. 1.1°×5.7°(15 units), 5.7°×5.7°(2 units), and blocked(1 unit). Therefore, the combined FOV of HE is approximately5.7°×5.7°. Each HE detector has a diameter of 190 mm resulting in a total geometrical area of approximately 5100 cm2, and the energy resolution is ~15% at 60 ke V. For each recorded X-ray event by HE, the timing accuracy is less than 10 μs and the deadtime is less than 10 μs. HE is used for observing spectra and temporal variability of X-ray sources in the 20-250 ke V band either by pointing observations for known sources or scanning observations to unveil new sources. Additionally, HE is used for monitoring the γ-ray burst in 0.2-3 Me V band. This paper not only presents the design and performance of HE instruments but also reports results of the on-ground calibration experiments.

关键词： X-ray telescope HXMT calibration scintillation detector

Milestone progress of the HEPS booster commissioning

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Nuclear Science and Techniques 2024年第1期35卷 170-177页

作者： Yue-Mei Peng Jian-She Cao Jin-Hui Chen Hai-Yi dong Ping He Yi Jiao ling Kang Wen Kang Jian li Jing-Yi li Guo-Ping lin Fang liu Feng-li Long Cai Meng Xin Qi Hua-Min Qu Yan-Feng Sui Sheng Wang Gang Xu Qiang Ye Jing zhang Pei zhang Wei-Min Pan key laboratory of particle Acceleration physics and Technology Institute of High Energy PhysicsChinese Academy of Sciences19B Yuquan RoadShijingshan DistrictBeijing 100049China University of the chinese academy of sciences 19A Yuquan RoadShijingshan DistrictBeijing 100049China

The high-energy photon source(HEPS)is the first fourth-generation synchrotron light source facility in *** HEPS injector consists of a linear accelerator(linac)and a full energy *** booster captures the electron beam from the linac and increases its energy to the value required for the storage *** full-energy beam could be injected to the storage ring directly or after“high-energy accumulation.”On November 17,2023,the key booster parameters successfully reached their corresponding target *** milestone results were achieved based on numerous contributions,including nearly a decade of physical design,years of equipment development and installation,and months of beam *** measured at the extraction energy of 6 GeV,the averaged beam current and emittance reached 8.57 mA with 5 bunches and 30.37 nm rad with a single-bunch charge of 5.58 nC,compared with the corresponding target values of 6.6 mA and 35 nm rad,*** paper presents the physical design,equipment development,installation,and commissioning process of the HEPS booster.

关键词： high energy photon source Booster Beam commissioning

Nondestructive technique for identifying nuclides using neutron resonance transmission analysis at CSNS Back-n

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Nuclear Science and Techniques 2024年第1期35卷 178-187页

作者： Sheng-Da Tang Yong-Hao Chen Jing-Yu Tang Rui-Rui Fan Qiang li Gong li dong liu Zheng-Yao Jin Xing-Zhu Cui Tian-Xiang Chen Yi-Wei Yang Rong liu Han Yi Yang li Zhen Yang Qi An Hao-Fan Bai Jiang-Bo Bai Jie Bao Ping Cao Qi-Ping Chen Zhen Chen Zeng-Qi Cui An-Chuan Fan Chang-Qing Feng Fan-Zhen Feng Ke-Qing Gao Min-Hao Gu Chang-Cai Han Zi-Jie Han Guo-Zhu He Yong-Cheng He Yang Hong Yi-Wei Hu Han-Xiong Huang Wei-Hua Jia Hao-yu Jiang Wei Jiang Zhi-jie Jiang ling Kang Bo li Chao li Jia-Wen li Xiao li Jie liu Shu-Bin liu Guang-Yuan Luan Chang-Jun Ning Bin-Bin Qi Jie Ren Zhi-Zhou Ren Xi-Chao Ruan Zhao-Hui Song Kang Sun Zhi-Xin Tan li-Jiao Wang Peng-Cheng Wang Zhao-Hui Wang Zhong-Wei Wen Xiao-Guang wu Xuan wu li-Kun Xie Yong-Ji Yu Guo-Hui zhang lin-Hao zhang Mo-Han zhang Qi-Wei zhang Xian-Peng zhang Yu-liang zhang Yue zhang Zhi-Yong zhang Mao-Yuan Zhao Lu-Ping Zhou Zhi-Hao Zhou Ke-Jun Zhu Sino-French institute of Nuclear Engineering and Technology Sun Yat-sen UniversityZhuhai 519082China institute of high-energy physics Chinese Academy of Sciences(CAS)Beijing 100049China Spallation Neutron Source Science Center Dongguan 523803China School of Nuclear Science and Technology University of Science and Technology of ChinaHefei 230026China State key laboratory of particle Detection and Electronics University of Science and Technology of ChinaHefei 230026China State key laboratory of particle Detection and Electronics Institute of High Energy PhysicsChinese Academy of SciencesBeijing 100049China USTC Archaeometry laboratory University of Science and Technology of ChinaHefei 230026China institute of Nuclear physics and Chemistry China Academy of Engineering PhysicsMianyang 621900China Department of Modern physics University of Science and Technology of ChinaHefei 230026China State key laboratory of Nuclear physics and Technology School of PhysicsPeking UniversityBeijing 100871China key laboratory of Nuclear Data China Institute of Atomic EnergyBeijing 102413China Northwest institute of Nuclear Technology Xi’an 710024China University of chinese academy of sciences Beijing 100049China

Nondestructive and noninvasive neutron assays are essential applications of neutron *** resonance transmission analysis(NRTA)is a powerful nondestructive method for investigating the elemental composition of an *** back-streaming neutron line(Back-n)is a newly built time-of-flight facility at the china Spallation Neutron Source(CSNS)that provides neutrons in the eV to 300 MeV range.A feasibility study of the NRTA method for nuclide identification was conducted at the CSNS Back-n via two test *** results demonstrate that it is feasible to identify different elements and isotopes in samples using the NRTA method at *** study reveals its potential future applications.

关键词： CSNS White neutron beam NRTA Nuclide identification Nondestructive method