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Status of the Hard X-ray Modulation Telescope Project

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空间科学学报 2016年第5期36卷 633-635页

作者： lu fangjun Institute of High Energy Physics Chinese Academy of Sciences

The Hard X-ray Modulation Telescope(HXMT) is China's first X-ray(1-250 keV)astronomical satellite officially approved in 2011.It will scan the Galactic plane to detect new transient sources and do pointed observations of X-ray sources to study their spectra and multiwavelength temporal properties.Now the flight model of the satellite is in the final testing stage,and the expected launch date is in late 2016.

关键词：硬X射线调制望远镜 X射线天文卫星 HXMT 时间属性 X射线源平面检测测试阶段飞行模型

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Status of the Hard X-ray Modulation Telescope(Insight-HXMT) Project

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空间科学学报 2018年第5期38卷 623-626页

作者： lu fangjun ZHANG Shuangnan Institute of High Energy Physics Chinese Academy of SciencesBeijing 100049

The Hard X-ray Modulation Telescope(HXMT) was launched at Jiuquan Satellite Launch Center on June 15, 2017, and was named as Insight-HXMT after the launch. Now all the instruments work properly in space, dozens of sources have been observed, and some early scientific results have been published. The nominal lifetime of Insight-HXMT is 4 years.

关键词：检查调整望远镜卫星发射中心工程

Simultaneous acceleration of sulfur reduction and oxidation on bifunctional electrocatalytic electrodes for quasi-solid-state Zn–S batteries

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Science China Chemistry 2024年第5期67卷 1531-1538页

作者： Mingli Wang Hong Zhang Tianhang Ding fangjun Wu Lin Fu Bin Song Pengfei Cao Ke lu Institutes of Physical Science and Information Technology School of Materials Science and EngineeringKey Laboratory of Structure and Functional Regulation of Hybrid Materials of Ministry of EducationAnhui UniversityHefei 230601China Hefei National Laboratory for Physical Sciences at the Microscale University of Science and Technology of ChinaHefei 230026China School of Chemistry and Chemical Engineering Harbin Institute of TechnologyHarbin 150001China School of Chemistry and Chemical Engineering Guizhou UniversityGuiyang 550025China Institute of Functional Nano&Soft Materials(FUNSOM) Soochow UniversitySuzhou 215123China State Key Lab of Organic-Inorganic Composites Beijing University of Chemical TechnologyBeijing 100029China

The incomplete sulfur reduction and high ZnS re-oxidation energy barrier along with severe side reactions during the battery cycling compromise the practical application of Zn–S electrochemistry. Herein, a bifunctional electrocatalytic sulfur matrix that simultaneously accelerates the sulfur reduction and ZnS oxidation is proposed to realize a highly-efficient Zn–S cell. It is revealed that the N-heteroatom hotspots are more favorable for facilitating the conversion of S to ZnS while the CoO nanocrystal substantially lowers the ZnS activation energy barrier thereby suppressing the formation of disproportionation species(e.g.,SO_(4)^(2-)) and accumulation of inactive ZnS. Accordingly, the Co O anchored on the N-doped carbon-supported sulfur cathode delivers a high Zn^(2+)storage capacity of 1,172 m Ahg^(-1)and outstanding cycling stability with a capacity retention of 71.6% after500 cycles with a high average Coulombic efficiency of 97.8%. Simultaneously, the stable cycling of solid-state Zn–S pouch cells with an energy density of 585 Whkg^(-1)sulfuris also demonstrated. Moreover, the postmortem analysis reveals that the degradation of Zn–S cells is mainly attributed to the limited reversibility of Zn anodes rather than the ZnS decomposition and/or accumulation. The approach to the bidirectional catalysis manipulated the sulfur redox provides a new perspective to realize the theoretical potentials of Zn–S cells.

关键词： Zn–S battery bifunctional catalysts solid-state battery sulfur redox degradation mechanism

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

Effect of orthokeratology on precision and agreement assessment of a new sweptsource optical coherence tomography biometer

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Eye and Vision 2020年第1期7卷 119-127页

作者： Bao Shu fangjun Bao Giacomo Savini Weicong lu Ruixue Tu Haisi Chen Benhao Song Qinmei Wang Jinhai Huang School of Ophthalmology and Optometry and Eye Hospital Wenzhou Medical University270 West Xueyuan RoadWenzhou 325027ZhejiangChina Key Laboratory of Vision Science Ministry of HealthWenzhouZhejiangPeople’s Republic of China G.B.Bietti Foundation IRCCS RomeItaly

Background:To evaluate the effect of orthokeratology on precision of measurements in children using a new swept-source optical coherence tomography(SS-OCT)optical biometer(OA-2000),and agreement between its measurements and those provided by the commonly used IOLMaster based on partial coherence interferometry(PCI).Methods:This study recruited fifty-one eyes of 51 normal children(8–16 years).An operator took measurements with the two biometers.Then,a second operator took measurements with the SS-OCT biometer.After orthokeratology was performed for one month,the same operators repeated the same procedures.Axial length(AL),mean keratometry(Km)at 2.5 mm and 3.0 mm diameters(Km2.5 and Km3.0),central corneal thickness(CCT),anterior chamber depth(ACD),lens thickness(LT)and corneal diameter(CD)were analyzed.Results:With the SS-OCT optical biometer,the test-retest repeatability of AL measurements was0.95.The 95%limits of agreement of difference between the two devices for CD parameter were up to 1.53 mm.After orthokeratology,the fluctuation ranges of difference for Km3.0 measurement was 1.11 times higher than before orthokeratology,while the absolute values of difference for AL,Km2.5,ACD and CD measurements were comparable.Conclusions:Before and after orthokeratology,the SS-OCT biometer showed high repeatability and reproducibility for all measurements.Wearing orthokeratology contact lenses affected the agreement between SS-OCT and PCI biometers for Km3.0 measurements.The CD measurement showed poor agreement between the two devices.

关键词： Swept source optical coherence tomography Orthokeratology Precision Agreement Children

Review of X-ray pulsar spacecraft autonomous navigation

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Chinese Journal of Aeronautics 2023年第10期36卷 44-63页

作者： Yidi WANG Wei ZHENG Shuangnan ZHANG Minyu GE Liansheng LI Kun JIANG Xiaoqian CHEN Xiang ZHANG Shijie ZHENG FangJun Lu College of Aerospace Science and Engineering National University of Defense TechnologyChangsha 410073China Key Laboratory of Particle Astrophysics Institute of High Energy PhysicsChinese Academy of SciencesBeijing 100049China University of Chinese Academy of Sciences Chinese Academy of SciencesBeijing 100049China Beijing Institute of Control Engineering Beijing 100080China Beijing Institute of Tracking and Communication Technology Beijing 100091China Aerospace Information Research Institute Chinese Academy of ScienceBeijing 100091China Academy of Military Science Beijing 100091China National Innovation Institute of Defense Technology Academy of Military ScienceBeijing 100091China

This article provides a review on X-ray pulsar-based navigation(XNAV).The review starts with the basic concept of XNAV,and briefly introduces the past,present and future projects concerning XNAV.This paper focuses on the advances of the key techniques supporting XNAV,including the navigation pulsar database,the X-ray detection system,and the pulse time of arrival estimation.Moreover,the methods to improve the estimation performance of XNAV are reviewed.Finally,some remarks on the future development of XNAV are provided.

关键词： Estimation of pulse time of arrival Spacecraft autonomous navigation X-ray detection X-ray pulsar-based navigation X-ray pulsar signal processing

Hard X-Ray Modulation Telescope(HXMT) Mission

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空间科学学报 2006年第z1期26卷 30-41页

作者： LI Tipei ZHANG Shuangnan lu fangjun Institute of High Energy Physics Chinese Academy of Sciences Beijing 100049 China Department of Engineering Physics Tsinghua University Department of Physics Tsinghua University Institute of High Energy Physics Chinese Academy of Sciences Beijing 100049 China

The HXMT mission concept consists of a slat-collimated hard X-ray detector assembly sensitive in 20～250 keV with a collection area of about 5000 cm2. Based on the reconstruction technique by direct demodulation developed in recent years, HXMT is mainly devoted to performing a hard X-ray all-sky imaging survey with both high sensitivity and high spatial resolution. It can also be used to make pointed observations of X-ray sources to study their spectroscopic and temporal properties in details. The main detector of HXMT consists of 18 individual cylindrical NaI(T1)/CsI(Na) phoswich modules, each with anarea of 283.5 cm2 and a field of view of 5.7°× 1.1° (FWHM). Its spatial resolution and position accuracy are 5′ and 1′ by using the direct demodulation in 1994, and in 2000 its feasibility and technical demonstration study was selected as a project under the Major State Basic Research Program of China. In October 2005, this project entered the full design phase and was listed as a candidate for the first dedicated astronomy satellite around 2010. We are now also considering secondary low energy instruments for this satellite.

关键词： Space Astronomy, Hard X-ray, Satellite

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

Hard X-ray Modulation Telescope

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Bulletin of the Chinese Academy of Sciences 2011年第3期25卷 235-236页

作者： lu fangjun a main technical principal of the HXMT project 不详

难 X 光检查调整望远镜 HXMT 将首先是瓷器天体的卫星。在 HXMT 上，有三种瞄准条板的望远镜，高精力X光检查望远镜他， 20-250 keV ， 5000 厘米^ 2 ，中等精力X光检查望远镜我， 5-30 keV ， 952 厘米^ 2 ，并且低精力X光检查望远镜... 详细信息

难 X 光检查调整望远镜 HXMT 将首先是瓷器天体的卫星。在 HXMT 上，有三种瞄准条板的望远镜，高精力X光检查望远镜他， 20-250 keV ， 5000 厘米^ 2 ，中等精力X光检查望远镜我， 5-30 keV ， 952 厘米^ 2 ，并且低精力X光检查望远镜 LE ， 1-15 keV ， 384 厘米^ 2 。

关键词：硬X射线调制望远镜 X射线望远镜准直望远镜天文卫星 HXMT 等能量低能量板式