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Observation of spectral lines in the exceptional GRB 221009A

Science China(Physics,Mechanics & Astronomy) 2024年第8期Mechanics & Astronomy) .卷 191-210页

作者： Yan-Qiu Zhang Shao-Lin xiong Ji-Rong Mao Shuang-Nan Zhang Wang-Chen Xue Chao Zheng Jia-Cong Liu Zhen Zhang xi-Lu Wang Ming-Yu Ge Shu-Xu Yi Li-Ming Song Zheng-Hua An Ce Cai xin-Qiao Li wen-xi peng wen-Jun Tan Chen-Wei Wang xiang-Yang wen Yue Wang Shuo xiao Fan Zhang peng Zhang Shi-Jie Zheng Key Laboratory of Particle Astrophysics Institute of High Energy PhysicsChinese Academy of Sciences University of Chinese Academy of Sciences Yunnan Observatories Chinese Academy of Sciences Center for Astronomical Mega-Science Chinese Academy of Sciences Key Laboratory for the Structure and Evolution of Celestial Objects Chinese Academy of Sciences College of Physics and Hebei Key Laboratory of Photophysics Research and Application Hebei Normal University Guizhou Provincial Key Laboratory of Radio Astronomy and Data Processing Guizhou Normal University College of Electronic and Information Engineering Tongji University

As the brightest gamma-ray burst ever observed, GRB 221009A provided a precious opportunity to explore spectral line features. In this article, we performed a comprehensive spectroscopy analysis of GRB 221009A jointly with GECAM-C and Fermi/GBM data to search for emission and absorption lines. For the first time we investigated the line feature throughout this GRB including the most bright part where many instruments suffered problems, and identified prominent emission lines in multiple time intervals. The central energy of the Gaussian emission line evolves from about 37 to 6 MeV, with a nearly constant ratio（about 10%） between the line width and central energy. Particularly, we find that both the central energy and the energy flux of the emission line evolve with time as a power law decay with power law index of –1 and –2, respectively. We suggest that the observed emission lines most likely origin from the blue-shifted electron positron pair annihilation 511 ke V line. We find that a standard high latitude emission scenario cannot fully interpret the observation, thus we propose that the emission line comes from some dense clumps with electron positron pairs traveling together with the jet. In this scenario, we can use the emission line to directly, for the first time, measure the bulk Lorentz factor of the jet（Γ） and reveal its time evolution(i.e., Γ～ t-1) during the prompt emission. Interestingly, we find that the flux of the annihilation line in the co-moving frame keeps constant. These discoveries of the spectral line features shed new and important lights on the physics of GRB and relativistic jet.

关键词： GRB GRB 221009A emission line

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A machine learning method to separate cosmic ray electrons from protons from 10 to 100 GeV using DAMPE data

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Research in Astronomy and Astrophysics 2018年第6期18卷 99-108页

作者： Hao Zhao wen-xi peng Huan-Yu Wang Rui Qiao Dong-Ya Guo Hong xiao Zhao-Min Wang Institute of High Energy Physics Chinese Academy of Sciences Beijing 100049 China University of Chinese Academy of Sciences Beijing 100049 China Changzhou Institute of Technology Changzhou 213032 China Gran Sasso Science Institute (GSSI) Via Iacobucci 2 I-67100 L'Aquila Italy Istituto Nazionale di Fisica Nucleare (INFN) Sezione di Lecce Via per Arnesano 1-73100 Lecce Italy

DArk Matter Particle Explorer(DAMPE) is a general purpose high energy cosmic ray and gamma ray observatory, aiming to detect high energy electrons and gammas in the energy range 5 Ge V to 10 Te V and hundreds of Te V for nuclei. This paper provides a method using machine learning to identify electrons and separate them from gammas, protons, helium and heavy nuclei with the DAMPE data acquired from 2016 January 1 to 2017 June 30, in the energy range from 10 to 100 Ge V.

关键词： astroparticle physics methods: data analysis cosmic rays

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Data processing for the Active Particle-induced X-ray Spectrometer and initial scientific results from Chang'e-3 mission

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Research in Astronomy and Astrophysics 2014年第12期14卷 1595-1606页

作者： xiao-Hui Fu Chun-Lai Li Guang-Liang Zhang Yong-Liao Zou Jian-Jun Liu xin Ren Xu Tan xiao-xia Zhang Wei Zuo Wei-Bin wen wen-xi peng xing-Zhu Cui Cheng-Mo Zhang Huan-Yu Wang National Astronomical Observatories Chinese Academy of Sciences Institute of High Energy Physics Chinese Academy of Sciences

The Active Particle-induced X-ray Spectrometer （APXS） is an important payload mounted on the Yutu rover, which is part of the Chang＇e-3 mission. The sci- entific objective of APXS is to perform in-situ analysis of the chemical composition of lunar soil and rock samples. The radioactive sources, 55Fe and 109Cd, decay and produce a-particles and X-rays. When X-rays and a-particles interact with atoms in the surface material, they knock electrons out of their orbits, which release energy by emitting X-rays that can be measured by a silicon drift detector （SDD）. The elements and their concentrations can be determined by analyzing their peak energies and in- tensities. APXS has analyzed both the calibration target and lunar soil once during the first lunar day and again during the second lunar day. The total detection time lasted about 266 min and more than 2000 frames of data records have been acquired. APXS has three operating modes： calibration mode, distance sensing mode and detection mode. In detection mode, work distance can be calculated from the X-ray counting rate collected by SDD. Correction for the effect of temperature has been performed to convert the channel number for each spectrum to X-ray energy. Dead time correction is used to eliminate the systematic error in quantifying the activity of an X-ray pulse in a sample and derive the real count rate. We report APXS data and initial results during the first and second lunar days for the Yutu rover. In this study, we analyze the data from the calibration target and lunar soil on the first lunar day. Seven major elements, including Mg, A1, Si, K, Ca, Ti and Fe, have been identified. Comparing the peak areas and ratios of calibration basalt and lunar soil the landing site was found to be depleted in K, and have lower Mg and A1 but higher Ca, Ti, and Fe. In the future, we will obtain the elemental concentrations of lunar soil at the Chang＇e-3 landing site using APXS data.

关键词： data analysis -- composition -- Moon

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Laboratory verification of the Active Particle-induced X-ray Spectrometer(APXS) on the Chang'e-3 mission

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Research in Astronomy and Astrophysics 2015年第11期15卷 1893-1904页

作者： Guang-Liang Zhang Chun-Lai Li xiao-Hui Fu Li-Yan Zhang Cao Ban Han Li Yong-Liao Zou wen-xi peng xing-Zhu Cui Cheng-Mo Zhang Huan-Yu Wang National Astronomical Observatories Chinese Academy of Sciences Key Laboratory of Lunar and Deep Space Exploration National Astronomical ObservatoriesChinese Academy of Sciences Institute of High Energy Physics Chinese Academy of Sciences

In the Chang＇e-3 mission, the Active Particle-induced X-ray Spectrometer（APXS） on the Yutu rover is used to analyze the chemical composition of lunar soil and rock samples. APXS data are only valid are only if the sensor head gets close to the target and integration time lasts long enough. Therefore, working distance and integration time are the dominant factors that affect APXS results. This study confirms the ability of APXS to detect elements and investigates the effects of distance and time on the measurements. We make use of a backup APXS instrument to determine the chemical composition of both powder and bulk samples under the conditions of different working distances and integration times. The results indicate that APXS can detect seven major elements, including Mg, Al, Si, K, Ca, Ti and Fe under the condition that the working distance is less than 30 mm and having an integration time of 30 min. The statistical deviation is smaller than 15%. This demonstrates the instrument＇s ability to detect major elements in the sample. Our measurements also indicate the increase of integration time could reduce the measurement error of peak area, which is useful for detecting the elements Mg, Al and Si. However, an increase in working distance can result in larger errors in measurement, which significantly affects the detection of the element Mg.

关键词： deviation rock lunar instrument verification backup rover detecting basalt enough

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Paired quasi-periodic pulsations of hard X-ray emission in a solar flare

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Science China(Physics,Mechanics & Astronomy) 2023年第5期66卷 195-206页

作者： Hai-Sheng Zhao Dong Li Shao-Lin xiong Yan-Qiu Zhang Yang Su Wei Chen Yi Zhao xiao-Bo Li Jia-Cong Liu wen-xi peng Rui Qiao xin-Qiao Li xiang-Yang wen Li-Ming Song Shi-Jie Zheng xin-Ying Song xiao-Yun Zhao Yue Huang Shuang-Nan Zhang Shuo xiao Ce Cai Zheng-Hua An Can Chen Gang Chen Wei Chen Yan-Qi Du Min Gao Ke Gong Dong-Ya Guo Zhi-Wei Guo Jian-Jian He Bin Li Chao Li Chao-Yang Li Gang Li Jian-Hui Li Lu Li Qing-xin Li Yan-Guo Li Jing Liang xiao-Hua Liang Jin-Yuan Liao xiao-Jing Liu Ya-Qing Liu Qi Luo xiang Ma Bin Meng Ge Ou Dong-Li Shi Jing-Yan Shi Gong-xing Sun xi-Lei Sun You-Li Tuo Chen-Wei Wang Hui Wang Jin Wang Jin-Zhou Wang Ping Wang wen-Shuai Wang Hong Wu Sheng-Lun xie Yan-Bing Xu Yu-peng Xu Wang-Chen Xue Sheng Yang Min Yao Jian-Ying Ye Qi-Bin Yi Chao-Yue Zhang Da-Li Zhang Fan Zhang Fei Zhang Hong-Mei Zhang Kai Zhang peng Zhang xiao-Lu Zhang Zhen Zhang Guo-Ying Zhao Shi-Yi Zhao Chao Zheng xing Zhou Yue Zhu Key Laboratory for Particle Astrophysics Institute of High Energy PhysicsChinese Academy of SciencesBeijing 100049China Purple Mountain Observatory Chinese Academy of SciencesNanjing 210023China University of Chinese Academy of Sciences Beijing 100049China Department of Astronomy Beijing Normal UniversityBeijing 100875China School of Computing and Artificial Intelligence Southwest Jiaotong UniversityChengdu 611756China Physics and Space Science College China West Normal UniversityNanchong 637002China Key Laboratory of Stellar and Interstellar Physics and Department of Physics Xiangtan UniversityXiangtan 411105China Institute of Astrophysics Central China Normal UniversityWuhan 430079China School of Physics Changchun University of Science and TechnologyChangchun 130022China College of Physics and Engineering Qufu Normal UniversityQufu 273165China College of Physics Sciences&Technology Hebei UniversityBaoding 071002China

We investigate high time resolution data obtained by the Gravitational wave high-energy Electromagnetic Counterpart All-sky Monitor(GECAM)during the flare event on 2022 April 21 at 01:52 UT.Several subpeaks with durations of 4-6 s have been detected in the hard X-ray precursor phase,and the key feature is that they appear in pairs and seem like double-peak struc-tures.These subpeaks are rarely observed in hard X-ray band and confirmed by the microwave obtained by Nobeyama Radio Polarimeters(NoRP)and Radio Solar Telescope Network(RSTN).While an exponential function can describe the continuum component of the time profile from the precursor to part of the impulsive phase.The periods of quasi-periodic pulsations(QPPs)are detected to be about 7.3 and 12.8 s for the precursor and impulsive phase,respectively,with at least 95%confidence level.The paired QPPs are assumed to be double-peak QPPs and then the scenario of current loop coalescence model is found to be in good agreement with our observation.The precursor phase can be interpreted as the oscillating coalescence of two islands,while the impulsive phase can be interpreted as more islands to coalesce one by one to form larger islands.

关键词： solar flare QPPs loop coalescence circular-ribbon flare

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Implications on the origin of cosmic rays in light of 10 TV spectral softenings

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Frontiers of physics 2020年第2期15卷 101-109,F0004页

作者： Cliuan Yue peng-xiong Ma Qiang Yuan Yi-Zhong Fan Zhan-Fang Chen Ming-Yang Cui Hao-Ting Dai Tie-Kuang Dong xiaoyuan Huang Wei Jiang Shi-Jun Lei xiang Li Cheng-Ming Liu Hao Liu Yang Liu Chuan-Ning Luo Xu Pan wen-xi peng Rui Qiao Yi-Feng Wei Li-Bo Wu Zhi-Hui Xu Zun-Lei Xu Guan-wen Yuan Jing-Jing Zang Ya-peng Zhang Yong-Jie Zhang Yun-Long Zhang Key Laboratory of Dark Matter and Space Astronomy Purple Mountain ObservatoryChinese Academy of SciencesNanjing 210033China School of Astronomy and Space Science University of Science and Technology of ChinaHefei 230026China Center for High Energy Physics Peking UniversityBeijing 100871China State Key Laboratory of Particle Detection and Electronics University of Science and Technology of ChinaHefei 230026China Key Laboratory of Particle Astrophysics Institute of High Energy PhysicsChinese Academy of SciencesBeijing 100049China Institute of Modem Physics Chinese Academy of SciencesLanzhou 730000China

Precise measurements of the energy spectra of cosmic rays(CRs)show various kinds of features deviating from single power-laws,which give very interesting and important implications on their origin and propagation.Previous measurements from a few balloon and space experiments indicate the existence of spectral softenings around 10 TV for protons(and probably also for Helium nuclei).Very recently,the DArk Matter Particle Explorer(DAMPE)measurement about the proton spectrum clearly reveals such a softening with a high significance.Here we study the implications of these new measurements,as well as the groundbased indirect measurements,on the origin of CRs.We find that a single component of CRs fails to fit the spectral softening and the air shower experiment data simultaneously.In the framework of multiple components,we discuss two possible scenarios,the multiple source population scenario and the background plus nearby source scenario.Both scenarios give reasonable fits to the wide-band data from TeV to 100 PeV energies.Considering the anisotropy observations,the nearby source model is favored.

关键词： cosmic rays

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Research on a multi‑dimensional image information fusion algorithm based on NSCT transform

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Frontiers of Optoelectronics 2024年第1期17卷 29-44页

作者： Yuxiang Su xi Liang Danhua Cao Zhenyu Yang Yuanlong peng Ming Zhao School of Optical and Electronic Information Huazhong University of Science and TechnologyWuhan 430074China State Grid Information and Telecommunication Branch Beijing 100761China

Traditional inspection cameras determine targets and detect defects by capturing images of their light intensity,but in complex environments,the accuracy of inspection may decrease.Information based on polarization of light can characterize various features of a material,such as the roughness,texture,and refractive index,thus improving classification and recognition of targets.This paper uses a method based on noise template threshold matching to denoise and preprocess polarized images.It also reports on design of an image fusion algorithm,based on NSCT transform,to fuse light intensity images and polarized images.The results show that the fused image improves both subjective and objective evaluation indicators,relative to the source image,and can better preserve edge information and help to improve the accuracy of target recognition.This study provides a reference for the comprehensive application of multi-dimensional optical information in power inspection.

关键词： Power inspection Object detection Polarization imaging Image fusion Image denoising

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Prenatal amoxicillin exposure induces developmental toxicity in fetal mice and its characteristics

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Journal of Environmental Sciences 2024年第3期137卷 287-301页

作者： Yongguo Dai Yu peng wen Hu Yi Liu Hui Wang Department of Pharmacology Wuhan University School of Basic Medical SciencesWuhan 430071China Department of Pharmacy Zhongnan Hospital of Wuhan UniversityWuhan 430071China Hubei Provincial Key Laboratory of Developmentally Originated Disease Wuhan 430071China

Amoxicillin,a widely used antibiotic in human and veterinary pharmaceuticals,is now considered as an“emerging contaminant”because it exists widespreadly in the environment and brings a series of adverse outcomes.Currently,systematic studies about the developmental toxicity of amoxicillin are still lacking.We explored the potential effects of amoxicillin exposure on pregnancy outcomes,maternal/fetal serum phenotypes,and fetal multiple organ development in mice,at different doses(75,150,300 mg/(kg·day))during late-pregnancy,or at a dose of 300 mg/(kg·day)during different stages(mid-/latepregnancy)and courses(single-/multi-course).Results showed that prenatal amoxicillin exposure(PAmE)had no significant infuence on the body weights of dams,but it could inhibit the physical development and reduce the survival rate of fetuses,especially during the midpregnancy.Meanwhile,PAmE altered multiple maternal/fetal serum phenotypes,especially in fetuses.Fetal multi-organ function results showed that PAmE inhibited testicular/adrenal steroid synthesis,long bone/cartilage and hippocampal development,and enhanced ovarian steroid synthesis and hepatic glycogenesis/lipogenesis,and the order of severity might be gonad(testis,ovary)>liver>others.Further analysis found that PAmE-induced multiorgan developmental and functional alterations had differences in stages,courses and fetal gender,and the most obvious changes might be in high-dose,late-pregnancy and multicourse,but there was no typical rule of a dose-response relationship.In conclusion,this study confirmed that PAmE could cause abnormal development and multi-organ function alterations,which deepens our understanding of the risk of PAmE and provides an experimental basis for further exploration of the long-term harm.

关键词： Amoxicillin Prenatal exposure Fetal development Organ function Developmental toxicity

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Coordination of distinctive pesticide adjuvants and atomization nozzles on droplet spectrum evolution for spatial drift reduction

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Chinese Journal of Chemical Engineering 2024年第2期66卷 250-262页

作者： Shidong Xue Jingkun Han xi xi Zhong Lan Rongfu wen Xuehu Ma State Key Laboratory of Fine Chemicals Liaoning Key Laboratory of Clean Utilization of Chemical ResourcesInstitute of Chemical EngineeringSchool of Chemical EngineeringDalian University of TechnologyDalian 16024China School of Fashion and Textiles The Hong Kong Polytechnic UniversityHong Kong 999077China China Tianchen Engineering Corporation Tianjin 300400China School of Energy and Power Engineering Dalian University of TechnologyDalian 116024China

Pesticide adjuvants,as crop protection products,have been widely used to reduce drift loss and improve utilization efficiency by regulating droplet spectrum.However,the coordinated regulation mechanisms of adjuvants and nozzles on droplet spectrum remain unclear.Here,we established the relationship between droplet spectrum evolution and liquid atomization by investigating the typical characteristics of droplet diameter distribution near the nozzle.Based on this,the regulation mechanisms of distinctive pesticide adjuvants on droplet spectrum were clarified,and the corresponding drift reduction performances were quantitively evaluated by wind tunnel experiments.It shows that the droplet diameter firstly shifts to the smaller due to the liquid sheet breakup and then prefers to increase caused by droplet interactions.Reducing the surface tension of sprayed liquid facilitates the uniform liquid breakup and increasing the viscosity inhibits the liquid deformation,which prolong the atomization process and effectively improve the droplet spectrum.As a result,the drift losses of flat-fan and hollow cone nozzles are reduced by about 50%after adding organosilicon and vegetable oil adjuvants.By contrast,the air induction nozzle shows a superior anti-drift ability,regardless of distinctive adjuvants.Our findings provide insights into rational adjuvant design and nozzle selection in the field application.

关键词： Pesticide drift Spray droplets Particle size distribution Spray atomization Transport processes Adjuvants

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Chemical Scissors Tailored Nano‑Tellurium with High‑Entropy Morphology for Efficient Foam‑Hydrogel‑Based Solar Photothermal Evaporators

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Nano-Micro Letters 2024年第3期16卷 149-168页

作者： Chenyang xing Zihao Li Ziao Wang Shaohui Zhang Zhongjian xie xi Zhu Zhengchun peng State Key Laboratory of Radio FrequencyHeterogeneous Integration Shenzhen UniversityShenzhen 518060People’s Republic of China Center for Stretchable Electronics and NanoSensors College of Physics and Optoelectronic EngineeringShenzhen UniversityShenzhen 518060People’s Republic of China School of Science and Engineering The Chinese University of Hong KongShenzhenShenzhen 518172People’s Republic of China Institute of Pediatrics Shenzhen Children’s HospitalShenzhen 518038GuangdongPeople’s Republic of China International Collaborative Laboratory of 2D Materials for Optoelectronics Science and Technology of Ministry of Education Institute of Microscale OptoelectronicsShenzhen UniversityShenzhen 518060People’s Republic of China

The development of tellurium(Te)-based semiconductor nanomaterials for efficient light-to-heat conversion may offer an effective means of harvesting sunlight to address global energy concerns.However,the nanosized Te(nano-Te)materials reported to date suffer from a series of drawbacks,including limited light absorption and a lack of surface structures.Herein,we report the preparation of nano-Te by electrochemical exfoliation using an electrolyzable room-temperature ionic liquid.Anions,cations,and their corresponding electrolytic products acting as chemical scissors can precisely intercalate and functionalize bulk Te.The resulting nano-Te has high morphological entropy,rich surface functional groups,and broad light absorption.We also constructed foam hydrogels based on poly(vinyl alcohol)/nano-Te,which achieved an evaporation rate and energy efficiency of 4.11 kg m^(−2)h^(−1)and 128%,respectively,under 1 sun irradiation.Furthermore,the evaporation rate was maintained in the range 2.5-3.0 kg m^(−2)h^(−1)outdoors under 0.5-1.0 sun,providing highly efficient evaporation under low light conditions.

关键词： Tellurium High entropy Electrochemical modification Solar absorption Evaporation rate

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