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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

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

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

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Radiation Detection Technology and Methods 2023年第1期7卷 25-33页

作者： Xiaobo Li Yong Chen Liming Song Weiwei Cui Wei Li Juan Wang Shuang-Nan Zhang fangjun lu Yupeng Xu Haisheng Zhao Mingyu Ge Youli Tuo Yusa Wang Tianxiang Chen Dawei Han Jia Huo Yanji Yang Maoshun Li Ziliang Zhang Yuxuan Zhu Xiaofan Zhao Key Laboratory of Particle Astrophysics Institute of High Energy PhysicsChinese Academy of Science19B Yuquan RoadShijingshan DistrictBeijing 100049China

Purpose The low-energy X-ray telescope(LE)is a main instrument of the Insight-HXMT mission and consists of 96 swept charge devices covering the 1–10 keV energy band.The energy gain and resolution are continuously calibrated by analyzing Cassiopeia A(Cas A)and blank sky data,while the effective areas are also calibrated with the observations of the Crab Nebula.In this paper,we present the evolution of the in-orbit performances of LE in the first 5 years since launch.Methods The Insight-HXMT data analysis software package(HXMTDAS)is utilized to extract the spectra of Cas A,blank sky,and Crab Nebula using different good time interval selections.We fit a model with a power-law continuum and several Gaussian lines to different ranges of Cas A and blank sky spectra to get peak energies of their lines through xspec.After updating the energy gain calibration in CALibration DataBase(CALDB),we rerun the Cas A data to obtain the energy resolution.An empirical function is used to modify the simulated effective areas so that the background-subtracted spectrum of the Crab Nebula can best match the standard model of the Crab Nebula.Results The energy gain,resolution,and effective areas are calibrated every month.The corresponding calibration results are duly updated in CALDB,which can be downloaded and used for the analysis of Insight-HXMT data.Simultaneous observations with NuSTAR and NICER can also be used to verify our derived results.Conclusion LE is a well-calibrated X-ray telescope working in 1–10 keV band.The uncertainty of LE gain is less than 20eV in 2–9 keV band,and the uncertainty of LE resolution is less than 15eV.The systematic errors of LE,compared to the model of the Crab Nebula,are lower than 1.5%in 1–10 keV.

关键词： X-ray Calibration SCD In-orbit performance

某两驱纯电乘用车差速器异响故障机理分析和解决

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车辆与动力技术 2024年第1期 55-60,64页

作者：陈辉鲁方俊程翔吴桂义无锡中车浩夫尔动力总成有限公司无锡214174

在国家“碳达峰、碳中和”大背景下,纯电动汽车是未来汽车发展趋势,差速器是汽车转向系统的重要零件,其NVH性能好坏直接影响整车驾驶品质.文中基于解决工程上遇到的整车双扭线呜呜异响问题,通过对整车左、右半轴支架和电驱动差速器轴承... 详细信息

在国家“碳达峰、碳中和”大背景下,纯电动汽车是未来汽车发展趋势,差速器是汽车转向系统的重要零件,其NVH性能好坏直接影响整车驾驶品质.文中基于解决工程上遇到的整车双扭线呜呜异响问题,通过对整车左、右半轴支架和电驱动差速器轴承壳体附件位置布置传感器,测量其振动和噪音信号并分析时域特征和音频数据,结合主观驾评结果,电驱动的差速器振动加速度出现瞬时冲击特征明显,差速器轴承壳体振动冲击幅值最大,同时结合电驱动总成台架故障复现测试,最终锁定电驱动差速器总成是造成整车双扭线呜呜异响的主要原因,制定优化策略并完成台架及整车验证,成功解决了问题.

关键词：差速器异响行星齿轮半轴齿轮行星齿轮轴垫片金属摩擦声

Introduction to the detection technology of Ali CMB polarization telescope

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Radiation Detection Technology and Methods 2017年第2期1卷 21-30页

作者： He Gao Congzhan Liu Zhangwei Li Yang Liu Yongping Li Siyu Li Hong Li Guanhua Gao fangjun lu Xinmin Zhang Institute of High Energy Physics Chinese Academy of SciencesBeijingChina University of Chinese Academy of Sciences BeijingChina

Background Ali CMB polarization telescope(AliCPT)project is a well-timed and well-planned ground-based CMB project in Ali(Nagri)area of Tibet,China.It has been approved at the end of 2016.Aims To give an introduction to the detection technology of AliCPT.Method The whole receiver of AliCPT is introduced and discussed,including the optics,the cryostat,the preliminary design of focal plane TES bolometers,multiplexing SQUID readout,and so on.Conclusions The raw sensitivity ofr will reach below 0.001 by 10-year observation as AliCPT project being carried out and upgraded.

关键词： Microwave polarization detection Transition-edge sensor Multiplexing SQUID readout

新能源汽车齿轴过盈压装对中间轴齿轮精度的影响研究

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汽车实用技术 2024年第3期49卷 75-79页

作者：郑海涛鲁方俊吴桂义周韬无锡中车浩夫尔动力总成有限公司江苏无锡214000

过盈压装工艺广泛应用于新能源汽车齿轴加工领域,由于该工艺涉及过盈压装可能会对齿轮精度造成一定的影响,进而导致电驱总成噪声、振动与声振粗糙度(NVH)水平下降。为了深入研究从动齿轮压装过盈量对中间轴齿轮精度的影响,基于0.03 mm和... 详细信息

过盈压装工艺广泛应用于新能源汽车齿轴加工领域,由于该工艺涉及过盈压装可能会对齿轮精度造成一定的影响,进而导致电驱总成噪声、振动与声振粗糙度(NVH)水平下降。为了深入研究从动齿轮压装过盈量对中间轴齿轮精度的影响,基于0.03 mm和0.1 mm两种不同的过盈量进行压装测试。结果显示,两种过盈压装均对齿轮累积的影响最大,分别约5μm和8μm,此外,中间轴齿轮齿向角度对压装力较为敏感,最大变化量约6.5μm。基于以上测试结果对比分析发现,齿轮累积及齿向角度随压装过盈量的变大而变大,严重影响齿轮精度;其他齿轮精度参数对过盈压装量并不敏感,其变化量基本一致。

关键词：新能源汽车齿轮轴过盈压装齿轮精度

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

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