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从天文学和物理学的发展理解科学方法的3次飞跃

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科技导报 2024年第10期42卷 55-64页

作者：张双南中国科学院高能物理研究所粒子天体物理中心北京100049

科学已经成为人类文明的重要组成部分,科学的3个要素分别是科学的目的、精神和方法。理解科学方法对于理解科学和发展科学至关重要。从天文学和物理学的发展过程以及其中的若干典型和里程碑事件(包括近年来几次天文学研究领域获得的诺... 详细信息

科学已经成为人类文明的重要组成部分,科学的3个要素分别是科学的目的、精神和方法。理解科学方法对于理解科学和发展科学至关重要。从天文学和物理学的发展过程以及其中的若干典型和里程碑事件(包括近年来几次天文学研究领域获得的诺贝尔物理学奖)展开分析,将科学方法的建立和发展归纳总结为科学方法的3次飞跃,即希腊古典和希腊化时期“从形而上学到实在精确的科学”、科学革命时期“从观察思辨的科学到实验科学”以及现代科学时期“从证实的科学到证伪的科学”。

关键词：科学史科学科学方法

X-Ray Fine Structure of a Limb Solar Flare Revealed by Insight-HXMT,RHESSI and Fermi

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Research in Astronomy and Astrophysics 2022年第5期22卷 47-55页

作者： Ping zhang Wei Wang Yang Su shuangnan zhang Liming Song Fangjun Lu Shu zhang Department of Physics and Technology Wuhan UniversityWuhan 430072China WHU-NAOC Joint Center for Astronomy Wuhan UniversityWuhan 430072China Purple Mountain Observatory of the Chinese Academy of Sciences Nanjing 210023China Institute of High Energy Physics Chinese Academy of SciencesBeijing 100049China

We conduct a detailed analysis of an M1.3 limb flare occurring on 2017 July 3,which have the X-ray observations recorded by multiple hard X-ray telescopes,including Hard X-ray Modulation Telescope(Insight-HXMT),Ramaty High Energy Solar Spectroscopic Imager(RHESSI),and the Fermi Gamma-ray Space Telescope(Fermi).Joint analysis has also used the extreme ultraviolet(EUV)imaging data from the Atmospheric Imaging Assembly(AIA)aboard the Solar Dynamic Observatory.The hard X-ray spectral and imaging evolution suggest a lower corona source,and the non-thermal broken power law distribution has a rather low break energy~15 keV.The EUV imaging shows a rather stable plasma configuration before the hard X-ray peak phase,and accompanied by a filament eruption during the hard X-ray flare peak phase.Hard X-ray image reconstruction from RHESSI data only shows one foot point source.We also determined the DEM for the peak phase by SDO/AIA data.The integrated EM beyond 10 MK at foot point onset after the peak phase,while the>10 MK source around reconnection site began to fade.The evolution of EM and hard X-ray source supports lower corona plasma heating after non-thermal energy dissipation.The combination of hard X-ray spectra and images during the limb flare provides the understanding on the interchange of non-thermal and thermal energies,and relation between lower corona heating and the upper corona instability.

关键词： Sun flares-Sun corona-Sun X-rays-gamma-rays-plasmas-radiation mechanisms non-thermal-radiation mechanisms thermal

In-orbit performance of ME onboard Insight-HXMT in the first 5 years

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Radiation Detection Technology and Methods 2023年第1期7卷 15-24页

作者： Ying Tan Xuelei Cao Weichun Jiang Xiaobo Li Bin Meng Wanchang zhang Sheng Yang Tao Luo Yudong Gu Liang Sun Xiaojing Liu Yuanyuan Du Jiawei Yang Yanjun Xu Jinyuan Liao Yupeng Xu Fangjun Lu Liming Song shuangnan zhang Key Laboratory of Particle Astrophysics Institute of High Energy PhysicsChinese Academy of Science19B Yuquan RoadShijingshan DistrictBeijing 100049China

Introduction The medium-energy X-ray telescope(ME)is a collimated X-ray telescope onboard the Insight hard X-ray modulation telescope(Insight-HXMT)satellite.It has 1728 Si-PIN pixels readout using 54 low noise application-specific integrated circuits(ASICs).ME covers the energy range of 5–30 keV and has a total detection area of 952cm2.The typical energy resolution of ME at the beginning of the mission is 3 keV at 17.8 keV(full width at half maximum,FWHM),and the time resolution is 255μs.In this study,we present the in-orbit performance of ME in its first 5 years of operation.Methods The performance of ME was monitored using onboard radioactive sources and astronomical X-ray objects.ME carries six 241Am radioactive sources for onboard calibration,which can continuously illuminate the calibration pixels.The long-term performance evolution of ME can be quantified using the properties of the accumulated spectra of the calibration pixels.In addition,observations of the Crab Nebula and the pulsar were used to check the long-term evolution of the detection efficiency as a function of energy.Conclusion After 5 years of operation,742cm2 of the Si-PIN pixelswere stillworking normally.The peak positions of 241Am emission lines gradually shifted to the high-energy region,implying a slow increase in ME gain of 1.43%.A comparison of the ME spectra of the Crab Nebula and the pulsar shows that the E–C relations and the redistribution matrix file are still acceptable for most data analysis works,and there is no detectable variation in the detection efficiency.

关键词： Hard X-ray Calibration Detector In-orbit performance

Detection of butt weld of laser-MIG hybrid welding of thin-walled profile for high-speed train

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Railway Sciences 2022年第1期1卷 98-113页

作者： Qingxiang Zhou Fang Liu Jingming Li Jiankui Li shuangnan zhang Guixi Cai Technical Engineering Department CRRC Qingdao Si fang Co.LtdQingdaoChina Analysis and Testing Center Institute of Metal ResearchChinese Academy of SciencesShenyangChina

Purpose–This study aims to solve the problem of weld quality inspection,for the aluminum alloy profile welding structure of high-speed train body has complex internal shape and thin plate thickness(2–4 mm),the conventional nondestructive testing method of weld quality is difficult to implement.Design/methodology/approach–In order to solve this problem,the ultrasonic creeping wave detection technology was proposed.The impact of the profile structure on the creeping wave detection was studied by designing profile structural test blocks and artificial simulation defect test blocks.The detection technology was used to test the actual welded test blocks,and compared with the results of X-ray test and destructive test(tensile test)to verify the accuracy of the ultrasonic creeping wave test results.Findings–It is indicated that that X-ray has better effect on the inspection of porosities and incomplete penetration defects.However,due to special detection method and protection,the detection speed is slow,which cannot meet the requirements of field inspection of the welding structure of aluminum alloy thin-walled profile for high-speed train body.It can be used as an auxiliary detection method for a small number of sampling inspection.The ultrasonic creeping wave can be used to detect the incomplete penetration welds with the equivalent of 0.25 mm or more,the results of creeping wave detection correspond well with the actual incomplete penetration defects.Originality/value–The results show that creeping wave detection results correspond well with the actual non-penetration defects and can be used for welding quality inspection of aluminum alloy thin-wall profile composite welding joints.It is recommended to use the echo amplitude of the 10 mm 30.2 mm 30.5 mm notch as the criterion for weld qualification.

关键词： High-speed train Aluminum alloy profile Laser-MIG hybrid welding Nondestructive inspection X-ray radiography Ultrasonic creeping wave detection

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Space Astronomy

空间科学学报 2022年第4期42卷 588-607页

作者： zhang shuangnan YI Shuxu Institute of High Energy Physics Chinese Academy of SciencesBeijing 100049

This chapter reports the recent progress on the space astronomy missions of China,including the following missions:currently operating in orbit,e.g.,DAMPE,Insight-HXMT,GECAM,Polar Light,GRID and Lobster-eye X-ray Satellite;approved and under development for launch in the next a couple of years,e.g.,SVOM and EP;planned experiments to be onboard China’s Space Station in the next several years,e.g.,CSST,HERD,POLAR-2,DIXE and Ly RIC;candidate missions that have passed the first round of review of Strategy Priority Program on space science(Ⅲ)of the Chinese Academy of Sciences,e.g.,eXTP,DAMPE-2,Earth 2.0,DSL and CHES.

关键词： Space science Space astronomy Satellite Space station

Study of linearity of LYSO crystal for the high energy cosmic radiation detection(HERD)facility

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Radiation Detection Technology and Methods 2017年第1期1卷 21-28页

作者： Zheng Quan Zhigang Wang Ming Xu Yongwei Dong Junjing Wang Guangpeng An Xin Liu Tianwei Bao Li zhang RuijieWang Junguang Lv Bobing Wu shuangnan zhang Key Laboratory of Particle Astrophysics Institute of High Energy PhysicsCASBeijing 100049China University of Chinese Academy of Sciences Beijing 100049China State Key Laboratory of Particle Detection and Electronics Institute of High Energy PhysicsCASBeijing 100049China

The high energy cosmic-radiation detection(HERD)facility is a space mission designed for detecting cosmic ray(CR)electrons,γ-rays up to tens of TeV and CR nuclei from proton to iron up to several PeV.The main instrument of HERD is a 3-D imaging calorimeter(CALO)composed of nearly ten thousand lutetium yttrium orthosilicate(LYSO,with cerium doping)crystal cubes.A large dynamic range of single HERD CALO Cell(HCC)is necessary to achieve HERD’s PeV observation objectives,which means that the response of HCC should maintain a good linearity from minimum ionizing particle(MIP)calibration to PeV shower maximum.In order to study the linearity ofHCC over such a large energy range,a beam test has been implemented at the E2 and E3 beam lines of BEPC.High intensity pulsed electron beam provided by E2 line is used for producing high energy density within HCC;π^(+)/proton provided by E3 line are used forHCCcalibration.The results showthat no saturation effect occurs and the linearity ofHCCis better than 10%from 30 MeV(1MIP)to 1.1×10^(3) TeV(energy density is 93 TeV/cm^(3)),which can meet the requirement mentioned above.

关键词： HERD Calorimeter LYSO Linearity Beam test

The Low Energy X-ray telescope (LE) onboard the Insight-HXMT astronomy satellite

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Science China(Physics,Mechanics & Astronomy) 2020年第4期63卷 49-61页

作者： Yong Chen WeiWei Cui Wei Li Juan Wang YuPeng Xu FangJun Lul YuSa Wang TianXiang Chen DaWei Han Wei Hu Yi zhang Jia Huo YanJi Yang MaoShun Li Bo Lu ZiLiang zhang TiPei Li shuangnan zhang ShaoLin Xiong Shu zhang RongFeng Xue XiaoFan Zhao Yue Zhu YuXuan Zhu HongWei Liu YiJung Yang Fan zhang Key Laboratory of Particle Astrophysics Institute of High Energy PhysicsChinese Academy of SciencesBeijing 100049China University of Chinese Academy of Sciences Beijing 100049China Department of Physics Tsinghua UniversityBeijing 100084China Department of Education Lu Liang UniversityLuliang 033000China Qian Xuesen Laboratory of Space Technology China Academy of Space TechnologyBeijing 100094China College of Physics Jilin UniversityChangchun 130023China

The Low Energy X-ray telescope(LE) is one of the three main instruments of the Insight-Hard X-ray Modulation Telescope(Insight-HXMT). It is equipped with Swept Charge Device(SCD) sensor arrays with a total geometrical area of 384 cm^2 and an energy band from 0.7 to 13 ke V. In order to evaluate the particle induced X-ray background and the cosmic X-ray background simultaneously, LE adopts collimators to define four types of Field Of Views(FOVs), i.e., 1.6°×6°, 4°×6°, 50°-60°×2°-6 oand the blocked ones which block the X-ray by an aluminum cover. LE is constituted of three detector boxes(LEDs) and an electric control box(LEB) and achieves a good energy resolution of 140 e V@5.9 ke V, an excellent time resolution of 0.98 ms, as well as an extremely low pileup(<1%@18000 cts/s). Detailed performance tests and calibration on the ground have been performed,including energy-channel relation, energy response, detection efficiency and time response.

关键词： LE X-ray telescope SCD collimators

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

The Medium Energy X-ray telescope (ME) onboard the Insight-HXMT astronomy satellite

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Science China(Physics,Mechanics & Astronomy) 2020年第4期63卷 35-48页

作者： XueLei Cao WeiChun Jiang Bin Meng WanChang zhang Tao Luo Sheng Yang ChunLei zhang YuDong Gu Liang Sun XiaoJing Liu JiaWei Yang Xian Li Ying Tan ShaoZhen Liu YuanYuan Du FangJun Lu YuPeng Xu Ju Guan shuangnan zhang HuanYu Wang TiPei Li ChengMo zhang XiangYang Wen JinLu Qu LiMing Song XiaoBo Li MingYu Ge YuPeng Zhou ShaoLin Xiong Shu zhang YongJie zhang ZeHao Cheng Fei zhang MaoShun Li XiaoHua Liang Min Gao EnBo Yang XiaoHang Liu 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 Beijing Key Laboratory of Space Thermal Control Technology Beijing Institute of Spacecraft System EngineeringBeijing 100094China Department of Modern Physics School of Physical SciencesUniversity of Science and Technology of ChinaHefei 230022China School of Physical Sciences Guizhou UniversityGuivang 550025China School of Opto-Electronic Information Science and Technology Yantai UniversityYantai 264005China University of Chinese Academy of Sciences Beijing 100049China

The Medium Energy X-ray telescope(ME) is one of the three main telescopes on board the Insight hard X-ray modulation telescope(Insight-HXMT) astronomy satellite. ME contains 1728 pixels of Si-PIN detectors sensitive in 5-30 ke V with a total geometrical area of 952 cm^2. The application specific integrated circuit(ASIC) chip, VA32TA6, is used to achieve low power consumption and low readout noise. The collimators define three kinds of field of views(FOVs) for the telescope, 1°×4°, 4°×4°,and blocked ones. Combination of such FOVs can be used to estimate the in-orbit X-ray and particle background components.The energy resolution of ME is ~3 ke V at 17.8 ke V(FWHM) and the time resolution is 255 μs. In this paper, we introduce the design and performance of ME.

关键词： Si-PIN ASIC medium energy X-ray