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Observation of spectral lines in the exceptional GRB 2.1009A

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Science china(physics,Mechanics & Astronomy) 2024年第8期67卷 187-206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-{2. 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 SciencesBeijing 100049China university of Chinese Academy of Sciences Beijing 100049China Yunnan Observatories Chinese Academy of SciencesKunming 650011China Center for Astronomical Mega-Science Chinese Academy of SciencesBeijing 100012China Key Laboratory for the Structure and Evolution of Celestial Objects Chinese Academy of SciencesKunming 650216China college of physics and Hebei Key Laboratory of Photophysics Research and Application Hebei Normal UniversityShijiazhuang 050024China Guizhou Provincial Key Laboratory of Radio Astronomy and Data Processing Guizhou Normal UniversityGuiyang 550001China college of Electronic and information {2. Tongji UniversityShanghai 201804China

As the brightest gamma-ray burst ever observed,GRB 2.1009A provided a precious opportunity to explore spectral line *** this article,we performed a comprehensive spectroscopy analysis of GRB 2.1009A jointly with GECAM-C and Fermi/GBM data to search for emission and absorption *** 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 *** 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 ***,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.*** suggest that the observed emission lines most likely origin from the blue-shifted electron positron pair annihilation 511 ke V *** 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 *** 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 ***,we find that the flux of the annihilation line in the co-moving frame keeps *** discoveries of the spectral line features shed new and important lights on the physics of GRB and relativistic jet.

关键词： GRB GRB 2.1009A emission line

Application of deep learning methods combined with physical background in wide field of view imaging atmospheric Cherenkov telescopes

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Nuclear Science and Techniques 2024年第4期35卷 208-220页

作者： Ao-Yan Cheng Hao Cai Shi Chen Tian-lu Chen Xiang Dong You-Liang Feng Qi Gao Quan-Bu Gou Yi-Qing Guo Hong-Bo Hu Ming-Ming Kang Hai-Jin Li Chen Liu mao-Yuan Liu Wei Liu Fang-Sheng Min Chu-Cheng Pan Bing-Qiang Qiao Xiang-Li Qian Hui-Ying Sun Yu-Chang Sun Ao-Bo {2. Xu {2. Zhen {2. Guang-Guang Xin Yu-Hua Yao Qiang Yuan Yi Zhang School of physics and Technology Wuhan UniversityWuhan 430072China School of physics and Astronomy Yunnan UniversityKunming 650091China Ministry of Education The Key Laboratory of Cosmic Rays(Tibet University)Lhasa 850000China Key Laboratory of Particle Astrophysics Institute of High Energy PhysicsChinese Academy of SciencesBeijing 100049China university of Chinese Academy of Sciences 19 A Yuquan RoadShijingshan DistrictBeijing 100049China college of physics Sichuan UniversityChengdu 610064China School of Intelligent engineering Shandong Management UniversityJinan 250357China Tsung‑Dao Lee Institute Shanghai Jiao Tong UniversityShanghai 200240China Suzhou Aerospace information Research Institute Suzhou 215123China college of physics Chongqing UniversityNo.55 Daxuecheng South RoadHigh‑tech DistrictChongqing 401331China Key Laboratory of Dark Matter and Space Astronomy Purple Mountain ObservatoryChinese Academy of SciencesNanjing 210008China

The High Altitude Detection of Astronomical Radiation(HADAR)experiment,which was constructed in Tibet,china,combines the wide-angle advantages of traditional EAS array detectors with the high-sensitivity advantages of focused Cherenkov *** objective is to observe transient sources such as gamma-ray bursts and the counterparts of gravitational *** study aims to utilize the latest AI technology to enhance the sensitivity of HADAR *** datasets and models with distinctive creativity were constructed by incorporating the relevant physical theories for various *** models can determine the type,energy,and direction of the incident particles after careful *** obtained a background identification accuracy of 98.6%,a relative energy reconstruction error of 10.0%,and an angular resolution of 0.2.°in a test dataset at 10 *** findings demonstrate the significant potential for enhancing the precision and dependability of detector data analysis in astrophysical *** using deep learning techniques,the HADAR experiment’s observational sensitivity to the Crab Nebula has surpassed that of MAGIC and *** energies below 0.5 TeV and remains competitive with conventional narrow-field Cherenkov telescopes at higher *** addition,our experiment offers a new approach for dealing with strongly connected,scattered data.

关键词： VHE gamma-ray astronomy HADAR Deep learning Convolutional neural networks

The In-Flight Realtime Trigger and Localization Software of GECAM

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Research in Astronomy and Astrophysics 2024年第10期24卷 11-24页

作者： Xiao-Yun Zhao Shao-Lin Xiong Xiang-Yang Wen Xin-Qiao Li Ce Cai Shuo Xiao Qi luo Wen-Xi Peng Dong-Ya Guo Zheng-Hua An Ke Gong Jin-Yuan Liao Yan-Qiu Zhang Yue Huang lu Li Xing Wen Fei Zhang Jing Duan Chen-Wei {2. Dong-Li Shi Peng Zhang Qi-Bin Yi Chao-Yang Li Yan-Bing Xu Xiao-Hua Liang Ya-Qing Liu Da-Li Zhang Xi-Lei Sun Fan Zhang Gang Chen Huan-Yu {2. Sheng Yang Xiao-Jing Liu Min Gao mao-Shun Li Jin-Zhou {2. Xing Zhou Yi Zhao {2.-Chen Xue Chao Zheng Jia-Cong Liu Xing-Bo Han Jin-Ling Qi Jia Huang Ke-Ke Zhang Can Chen Xiong-Tao Yang Dong-Jie Hou Yu-Sa {2. Rui Qiao Xiang Ma Xiao-Bo Li Ping {2. Xin-Ying Song Li-Ming Song Shi-Jie Zheng Bing Li Hong-Mei Zhang Yue Zhu Wei Chen Jian-Jian He Zhen Zhang Jin Hou Hong-Jun {2. Yan-Chao Hao Xiang-Yu {2. Zong-Yuan Yang Zhi-Long Wen Zhi Chang Yuan-Yuan Du Rui Gao Xiao-Fei Lan Yan-Guo Li Gang Li Xu-Fang Li Fang-Jun lu Hong lu Bin Meng Feng Shi Hui {2. Hui-Zhen {2. Yu-Peng Xu Jia-Wei Yang Xue-Juan Yang Shuang-Nan Zhang Chao-Yue Zhang Cheng-Mo Zhang Zhi-Cheng Tang Cheng Cheng 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 School of information Science and Technology Southwest Jiaotong UniversityChengdu 611756China Key Laboratory of Stellar and Interstellar physics and Department of physics Xiangtan UniversityXiangtan 411105China physics and Space Science college China West Normal UniversityNanchong 637002China Department of Astronomy Beijing Normal UniversityBeijing 100875China Innovation Academy for Microsatellites of CAS Shanghai 201203China Changchun university of Science and Technology Changchun 130022China Chinese Academy of Sciences South America Center for Astronomy National Astronomical ObservatoriesCASBeijing 100101China

Realtime trigger and localization of bursts are the key functions of GECAM,an all-sky gamma-ray monitor launched on 2.2. December *** developed a multifunctional trigger and localization software operating in the CPU of the GECAM Electronic *** onboard software has the following features:high trigger efficiency for real celestial bursts with a suppression of false triggers caused by charged particle bursts and background fluctuation,dedicated localization algorithm optimized for both short and long bursts,and low time latency of the trigger information which is downlinked through the Global Short Message Communication service of the global BeiDou navigation *** paper provides a detailed description of the design and development of the trigger and localization software system for *** covers the general design,workflow,the main functions,and the algorithms used in the *** paper also includes on-ground trigger tests using simulated gamma-ray bursts generated by a dedicated X-ray tube,as well as an overview of the performance for real celestial bursts during its in-orbit operation.

关键词： telescopes instrumentation:detectors methods:observational

Field induced Chern insulating states in twisted monolayer–bilayer graphene

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Chinese physics B 2024年第6期33卷 69-73页

作者：王政文韩英卓 Kenji Watanabe Takashi Taniguchi 姜宇航毛金海 School of Physical Science and CAS Center for Excellence in Topological Quantum Computation University of Chinese Academy of SciencesBeijing 100049China college of Materials Science and Optoelectronic Technology Center of Materials Science and Optoelectronics EngineeringUniversity of Chinese Academy of SciencesBeijing 100049China Advanced Materials Laboratory National Institute for Materials ScienceTsukuba 305-0044Japan

Unraveling the mechanism underlying topological phases, notably the Chern insulators(Ch Is) in strong correlated systems at the microscopy scale, has captivated significant research interest. Nonetheless, Ch Is harboring topological information have not always manifested themselves, owing to the constraints imposed by displacement fields in certain experimental configurations. In this study, we employ density-tuned scanning tunneling microscopy(DT-STM) to investigate the Ch Is in twisted monolayer–bilayer graphene(t MBG). At zero magnetic field, we observe correlated metallic *** under a magnetic field, a metal–insulator transition happens and an integer Ch I is formed emanating from the filling index s = 3 with a Chern number C = 1. Our results underscore the pivotal role of magnetic fields as a powerful probe for elucidating topological phases in twisted Van der Waals heterostructures.

关键词： Chern insulators strong correlation effects two-dimensional van der Waals heterostructure density-tuned scanning tunneling microscopy(DT-STM)

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共同信号驱动半导体激光器相位混沌同步

激光与光电子学进展 2024年第15期61卷 199-207页

作者：王静毛晓鑫王龙生王安帮太原理工大学新型传感器与智能控制教育部重点实验室山西太原030024 太原理工大学物理与光电工程学院山西太原030024 广东工业大学广东省信息光子技术重点实验室广东广州510006

提出一种基于共同信号驱动半导体激光器的相位混沌同步方法。该方法避免了传统主从同步结构中外腔模式跳变对相位差的影响,提高了相位混沌同步的稳定性。在背靠背条件下,探明了实现稳定的相位混沌同步的参数条件:当注入强度为0.15、光... 详细信息

提出一种基于共同信号驱动半导体激光器的相位混沌同步方法。该方法避免了传统主从同步结构中外腔模式跳变对相位差的影响,提高了相位混沌同步的稳定性。在背靠背条件下,探明了实现稳定的相位混沌同步的参数条件:当注入强度为0.15、光频失谐为-2.GHz、激光器线宽为2.5 MHz时,可获得相位差标准偏差为0.015π的相位混沌同步。进一步分析了长距离光纤传输对相位混沌同步稳定性的影响,在160 km光纤传输下获得了标准偏差为0.04π的稳定相位混沌同步。

关键词：半导体激光器混沌激光混沌同步相位同步保密通信

电子在自旋-轨道耦合调制下磁受限半导体纳米结构中的传输时间及其自旋极化

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物理学报 2024年第11期73卷 377-384页

作者：温丽卢卯旺陈嘉丽陈赛艳曹雪丽张安琪桂林理工大学物理与电子信息工程学院桂林541004

通过考虑构筑在半导体GaAs/Al_(x)Ga_(1–x)As异质结上的磁受限半导体纳米结构中的塞曼效应和自旋-轨道耦合,本文采用理论分析和数值计算相结合的方法研究了电子的传输时间与自旋极化.利用矩阵对角化和改进的转移矩阵方法,数值求解电子... 详细信息

通过考虑构筑在半导体GaAs/Al_(x)Ga_(1–x)As异质结上的磁受限半导体纳米结构中的塞曼效应和自旋-轨道耦合,本文采用理论分析和数值计算相结合的方法研究了电子的传输时间与自旋极化.利用矩阵对角化和改进的转移矩阵方法,数值求解电子的薛定谔方程;采用***理论求电子的居留时间,并计算自旋极化率.由于塞曼效应与自旋-轨道耦合,电子的居留时间明显地与其自旋有关,因此可在时间维度上分离自旋、实现半导体中电子的自旋极化.因为半导体GaAs的有效g-因子很小,电子自旋极化主要源于自旋-轨道耦合,大约为塞曼效应引起的自旋极化的4倍.由于电子的有效势与自旋-轨道耦合的强度有关,电子的居留时间及其自旋极化可通过界面限制电场或应力工程进行有效调控.这些有趣的结果不仅对半导体自旋注入具有参考价值,而且还可为半导体自旋电子学器件应用提供时间电子自旋分裂器.

关键词：半导体自旋电子学磁调制半导体纳米结构自旋-轨道耦合居留时间

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智能近远光灯系统的研究

科技资讯 2024年第13期22卷 56-58页

作者：王璐毛自娟卢雨菲罗冰艳兴义民族师范学院物理与工程技术学院贵州兴义562400

随着现代城市化进程的不断加速,人们的日常生活与消费需求的变迁,交通安全问题成为了人们关注的重要议题。以传统车灯为基础,并添加了人工智能(Artificial Intelligence,AI)技术,旨在降低因使用近远光灯不当所导致的交通事故风险,从而... 详细信息

随着现代城市化进程的不断加速,人们的日常生活与消费需求的变迁,交通安全问题成为了人们关注的重要议题。以传统车灯为基础,并添加了人工智能(Artificial Intelligence,AI)技术,旨在降低因使用近远光灯不当所导致的交通事故风险,从而保障出行安全。系统采用单片机为控制核心,太阳能供电,使用光敏电阻检测光照强度,并可进行自动、手动模式转换,舵机用于控制灯光的角度。单片机可接收信息并驱动转换系统对车灯进行精细控制。研究设计的智能车灯系统能够合理地根据道路光照情况使用车灯,有效避免人为原因所导致的事故风险,并能大幅度减少能源的浪费,从而实现低碳环保的目标。

关键词：近远光灯舵机太阳能自动转换交通安全

A draft sequence of the rice (Oryza sativa ssp. indica) genome

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Chinese Science Bulletin 2001年第23期46卷 1937-1942页

The sequence of the rice genome holds fundamental information for its biology, including physiology, genetics, development, and evolution, as well as information on many beneficial phenotypes of economic significance. Using a "whole genome shotgun" approach, we have pro-duced a draft rice genome sequence of Oryza sativa ssp. in-dica, the major crop rice subspecies in china and many other regions of Asia. The draft genome sequence is constructed from over 4.3 million successful sequencing traces with an accumulative total length of 2.14.9 Mb. The initial assembly of the non-redundant sequences reached 409.76 Mb in length, based on 3.30 million successful sequencing traces with a total length of 1797.4 Mb from an indica variant cultivar 93-11, giving an estimated coverage of 95.2.% of the rice genome with an average base accuracy of higher than 99%. The coverage of the draft sequence, the randomness of the sequence distribution, and the consistency of BIG-ASSEM-BLER, a custom-designed software package

关键词： rice genome draft sequences.

Internet Multimedia Traffic Classification from QoS Perspective Using Semi-Supervised Dictionary Learning Models

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china Communications 2017年第10期14卷 202-218页

作者： Zaijian wang Yuning Dong Shiwen mao Xinheng wang college of physics and Electronic {2. Anhui Normal University Wuhu 241000 China college of Communications and information {2. Nanjing University of Posts and Telecommunications Nanjing 210003 China Department of Electrical and Computer engineering Auburn University Auburn AL 36849-5201 USA School of Computing University of the West of Scotland Paisley PA 1 2BE UK

To address the issue of finegrained classification of Internet multimedia traffic from a Quality of Service(QoS) perspective with a suitable granularity, this paper defines a new set of QoS classes and presents a modified K-Singular Value Decomposition(K-SVD) method for multimedia identification. After analyzing several instances of typical Internet multimedia traffic captured in a campus network, this paper defines a new set of QoS classes according to the difference in downstream/upstream rates and proposes a modified K-SVD method that can automatically search for underlying structural patterns in the QoS characteristic space. We define bagQoS-words as the set of specific QoS local patterns, which can be expressed by core QoS characteristics. After the dictionary is constructed with an excess quantity of bag-QoSwords, Locality Constrained Feature Coding(LCFC) features of QoS classes are extracted. By associating a set of characteristics with a percentage of error, an objective function is formulated. In accordance with the modified K-SVD, Internet multimedia traffic can be classified into a corresponding QoS class with a linear Support Vector Machines(SVM) clas-sifier. Our experimental results demonstrate the feasibility of the proposed classification method.

关键词： dictionary learning traffic classication multimedia traffic K-singular value decomposition quality of service