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Probing dark matter particles from evaporating primordial black holes via electron scattering in the CDEX-10 experiment

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Science China(Physics,Mechanics & Astronomy) 2024年第10期Mechanics & Astronomy) .卷 87-95页

作者： Zhenhua Zhang litao Yang Qian yue Kejun Kang yuanjing li Haipeng An Greeshma C. jianping Chang yunhua Chen jianping cheng Wenhan Dai Zhi Deng Changhao Fang Xinping Geng Hui Gong Qiuju Guo Tao Guo Xuyuan Guo li He Shengming He jinwei Hu Hanxiong Huang Tuchen Huang lin jiang S.Karmakar Haubin li Hanyu li jianmin li jin li Qianyun li Renmingjie li xueqian li yulan li Yifan liang Bin liao FongKay lin ShinTed lin jiaxuan liu Shukui liu Yandong liu yu liu yuanyuan liu Hao Ma yucai mao Qiyuan Nie jinhua Ning Hui pan Ningchun Qi jie Ren Xichao Ruan Monoj Kumar Singh tianxi Sun Changjian tang Yang tian Guangfu Wang Junzheng Wang li Wang Qing Wang yufeng Wang yunxiang Wang Henry Tsz-King Wong Shiyong Wu yucheng Wu Haoyang Xing Rui Xu Yin Xu Tao xue yulu Yan Nan Yi Chunxu yu Haijun yu jianfeng yue Ming Zeng Zhi Zeng Bingtao Zhang fengshou Zhang Lei Zhang Zhenyu Zhang jizhong Zhao Kangkang Zhao Minggang Zhao jifang Zhou Zuying Zhou jingjun Zhu CDEX Collaboration Key Laboratory of Particle and Radiation Imaging (Ministry of Education) and Department of Engineering Physics Tsinghua University Department of Physics Tsinghua University Institute of Physics Academia Sinica NUCTECH Company YaLong River Hydropower Development Company College of Nuclear Science and Technology Beijing Normal University College of Physics Sichuan University School of Physics Peking University Department of Nuclear Physics China Institute of Atomic Energy Sino-French Institute of Nuclear and Technology Sun Yet-sen University School of Physics Nankai University Department of Physics Banaras Hindu University Department of Physics Beijing Normal University

Dark matter（DM） is a major constituent of the ***,no definite evidence of DM particles（denoted as “χ”） has been found in DM direct detection（DD） experiments to *** is a novel concept of detectingχfrom evaporating primordial black holes（PBHs）.We search forχemitted from PBHs by investigating their interaction with target *** examined PBH masses range from 1×1015to 7×1016g under the current limits of PBH abundance *** 205.4 kg·day data obtained from the CDEX-10 experiment conducted in the China jinping Underground Laboratory,we exclude the χ-electron（χ-e） elastic-scattering cross section σχe～5×10-29cm2for χ with a mass ■ keV from our *** the higher radiation background but lower energy threshold（160 eV）,CDEX-10 fills a part of the gap in the previous *** (mχ,σχe) can be determined in the future,DD experiments are expected to impose strong constraints on fPBHfor large MPBHs.

关键词： CDEX primordial black hole light dark matter particle dark matter-electron scattering high purity germanium detector

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Channelmeasurements and models for 6G:current status and future outlook

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Frontiers of Information Technology & Electronic Engineering 2020年第1期21卷 39-61页

作者： jian-hua ZHANG pan tang li yu Tao jiang Lei tian State Key Lab of Networking and Switching Technology Beijing University of Posts and TelecommunicationsBeijing 100876China

With the commercialization of fifth generation networks worldwide,research into sixth generation(6G)networks has been launched to meet the demands for high data rates and low latency for future services.A wireless propagation channel is the transmission medium to transfer information between the transmitter and the ***,channel properties determine the ultimate performance limit of wireless communication ***,conducting channel research is a prerequisite to designing 6G wireless communication *** this paper,we first introduce several emerging technologies and applications for 6G,such as terahertz communication,industrial Internet of Things,space-air-ground integrated network,and machine learning,and point out the developing trends of 6G channel ***,we give a review of channel measurements and models for the technologies and ***,the outlook for 6G channel measurements and models is discussed.

关键词： Channel measurements Channel models Sixth generation Terahertz Industrial Internet of Things Space-air-ground integrated network Machine learning

Astudy of uplink and downlink channel spatial characteristics in an urban micro scenario at 28GHz

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Frontiers of Information Technology & Electronic Engineering 2021年第4期22卷 488-502页

作者： Tao jiang jianhua ZHANG pan tang Lei tian State Key Lab of Networking and Switching Technology Beijing University of Posts and TelecommunicationsBeijing 100876China

This paper presents an empirical study of the uplink and downlink azimuth angle of arrival(AoA)in an urban micro(UMi)scenario at 28 *** present,most UMi measurements are conducted in the downlink and then the uplink situation is inferred assuming channel *** the channel correlation coefficient of the uplink and downlink can be as high as 0.8,this does not mean that they are the *** a real uplink measurement can accurately describe its channel conditions,and this is what this study does.A receiver equipped with a rotatable horn antenna is mounted at the base station and the user terminal,respectively,in simulating the uplink and *** improve the angular resolution,we extract the multipath components(MPCs)using the space-alternating generalized expectation-maximization ***,a spatial lobe approach is used to cluster the MPCs in the power angular *** matching MPCs with objects in the environment,we find that direct propagation and first-order reflections are dominant in line-of-sight and non-line-of-sight *** comparing our measurement with those in standard channel models,we verify that the AoA of clusters follows a Gaussian distribution in the uplink and *** addition,a two-dimensional Gaussian distribution for ray AoA and power is established to reflect their correlation.

关键词： Channel measurements Millimeter-wave(mmWave) Uplink Downlink Azimuth angle of arrival

CEPC Technical Design Report

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Radiation Detection Technology and Methods 2024年第1期8卷 I0003-I0016,1-1091页

作者： Waleed Abdallah Tiago Carlos Adorno de Freitas Konstantin Afanaciev Shakeel Ahmad Ijaz Ahmed Xiaocong Ai Abid Aleem Wolfgang Altmannshofer Fabio Alves Weiming An Rui An Daniele Paolo Anderle Stefan Antusch Yasuo Arai Andrej Arbuzov Abdesslam Arhrib Mustafa Ashry Sha Bai yu Bai Yang Bai Vipul Bairathi Csaba Balazs Philip Bambade Yong Ban Tripamo Bandyopadhyay Shou-Shan Bao Desmond P.Barber Ayse Bat Varvara Batozskaya Subash Chandra Behera Alexander Belyaev Michele Bertucci Xiao-Jun Bi yuanjie Bi tianjian Bian Fabrizio Bianchi Thomas Biekotter Michela Biglietti Shalva Bilanishvili Deng Binglin Denis bodrov Anton bogomyagkov Serge bondarenko Stewart boogert Maarten boonekamp Marcello borri Angelo bosotti Vincent boudry Mohammed boukidi Igor boyko Ivanka bozovic Giuseppe bozzi Jean-Claude Brient Anastasiia Budzinskaya Masroor Bukhari Vladimir Bytev Giacomo Cacciapaglia Hua Cai Wenyong Cai Wujun Cai Yijian Cai Yizhou Cai yuchen Cai Haiying Cai Huacheng Cai Lorenzo Calibbi Junsong Cang Guofu Cao jianshe Cao Antoine Chance xuejun Chang yue Chang Zhe Chang Xinyuan Chang Wei Chao Auttakit Chatrabhuti Yimin Che yuzhi Che Bin Chen Danping Chen Fuqing Chen Fusan Chen Gang Chen Guoming Chen Hua-Xing Chen Huirun Chen jinhui Chen ji-yuan Chen Kai Chen Mali Chen Mingjun Chen Mingshui Chen Ning Chen Shanhong Chen Shanzhen Chen Shao-Long Chen Shaomin Chen Shiqiang Chen tianlu Chen Wei Chen Xiang Chen Xiaoyu Chen Xin Chen Xun Chen Xurong Chen Ye Chen Ying Chen yukai Chen Zelin Chen Zilin Chen Gang Chen boping Chen Chunhui Chen Hok Chuen cheng Huajie cheng Shan cheng Tongguang cheng yunlong Chi Pietro Chimenti Wen Han Chiu Guk Cho Ming-Chung Chu Xiaotong Chu Ziliang Chu Guglielmo Coloretti Andreas Crivellin Hanhua Cui Xiaohao Cui Zhaoyuan Cui Brunella D'Anzi ling-yun Dai Xinchen Dai Xuwen Dai Antonio De Maria Nicola De Filippis Christophe De La Taille Francesca De Mori Chiara De Sio Elisa Del Core Shuangxue Deng Wei-tian Deng Zhi Deng Ziyan Deng Bhupal Dev tang Dewen Biagio Di Micco Ran Ding Siqin Dingl Yadong Ding Haiyi Dong jianin AGH University of Science and Technology Faculty of Physics and Applied Computer ScienceKrakow Anhui University HefeiAnhui Applied Physics Department Federal Urdu University of ArtsScience and TechnologyIslamabad Banaras Hindu University Institute of ScienceVaranasi Bandirma Onyedi Eylul University Bandirma Beihang University Beijing Beijing Computational Science Research Center Beijing Beijing Conveyi LTD Beijing Beijing Glass Research Institute Co. LtdBeijing Beijing Institute of Technology Beijing Beijing Normal University Beijing Brown University ProvidenceRI Budker Institute of Nuclear Physics Novosibirsk Cadi Ayyad University Laboratory of Fundamental and Applied PhysicsPolydisciplinary FacultyMarrakech Cairo University Giza Center for Theory and Computation National Tsing Hua UniversityHsinchu Central China Normal University WuhanHubei Central South University ChangshaHunan Centro de Fisica Teorica de Particulas Universidade Tecnica de LisboaLisboa chengdu KaitengSifang Digital Radio&TV Equipment Co. LtdChengduSichuan China academy of engineering physics MianyangSichuan China building materials academy Beijing China Center of Advanced Science and Technology Beijing China Institute of Atomic Energy Beijing China jiliang University HangzhouZhejiang China Nuclear Instrument CO. LTDBeijing China University of Geosciences Beijing China University of Geosciences WuhanHubei China University of Mining and Technology XuzhouJiangsu China West Normal University NanchongSichuan Chongqing University Department of PhysicsChongqing Chulalongkorn University Bangkok City University of hong Kong Department of PhysicsHong Kong Cockcroft Institute Daresbury Cornell University IthacaNY CPPM(AMU/IPhU&CNRS/INP) Marseille Dalian Minzu University DalianLiaoning Dalian University of Technology Department of PhysicsDalian Deutsches Elektronen-Synchrotron DESY Hamburg Dzhelepov Laboratory of Nuclear Problems of Joint Institute for Nuclear Research(DLNP jiNR) Dubna East China University Of Science And Technol

The Circular Electron Positron Collider(CEPC)is a large scientific project initiated and hosted by China,fostered through extensive collaboration with international *** complex comprises four accelerators:a 30 GeV linac,a 1.1 GeV Damping Ring,a booster capable of achieving energies up to 180 GeV,and a Collider operating at varying energy modes(Z,W,H,and tt).The linac and Damping Ring are situated on the surface,while the subterranean booster and Collider are housed in a 100 km circumference underground tunnel,strategically accommodating future expansion with provisions for a potential Super Proton Proton Collider(SPPC).The CEPC primarily serves as a Higgs *** its baseline design with synchrotron radiation(SR)power of 30 MW per beam,it can achieve a luminosity of 5×10^(34)cm^(-2)s^(-1)per interaction point(IP),resulting in an integrated luminosity of 13 ab^(-1)for two IPs over a decade,producing 2.6 million Higgs *** the SR power to 50 MW per beam expands the CEPC's capability to generate 4.3 million Higgs bosons,facilitating precise measurements of Higgs coupling at sub-percent levels,exceeding the precision expected from the HL-LHC by an order of *** Technical Design Report(TDR)follows the Preliminary Conceptual Design Report(Pre-CDR,2015)and the Conceptual Design Report(CDR,2018),comprehensively detailing the machine's layout,performance metrics,physical design and analysis,technical systems design,R&D and prototyping efforts,and associated civil engineering ***,it includes a cost estimate and a preliminary construction timeline,establishing a framework for forthcoming engineering design phase and site selection *** is anticipated to begin around 2027-2028,pending government approval,with an estimated duration of 8 *** commencement of experiments and data collection could potentially be initiated in the mid-2030s.

关键词： initiated exceeding precise

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基于深度学习的SAR弱小目标检测研究进展

计算机系统应用 2024年第6期33卷 1-15页

作者：赵志成蒋攀王福田肖云李成龙汤进安徽大学人工智能学院合肥230601 安徽大学计算机科学与技术学院合肥230601

随着合成孔径雷达(SAR)技术的不断进步,大范围观测和高分辨率成像使得SAR图像中包含了大量特征微弱的小尺寸目标,通常涵盖飞机、车辆、油罐、船舶等高价值民用目标和关键军事目标,这类目标尺寸较小、特征微弱、稠密相连、形态多变,对它... 详细信息

随着合成孔径雷达(SAR)技术的不断进步,大范围观测和高分辨率成像使得SAR图像中包含了大量特征微弱的小尺寸目标,通常涵盖飞机、车辆、油罐、船舶等高价值民用目标和关键军事目标,这类目标尺寸较小、特征微弱、稠密相连、形态多变,对它们进行精确的检测是当前SAR图像解译的难题.随着深度学习技术的发展,研究者们针对SAR弱小目标的成像特性和检测挑战,通过对深度学习网络的精细调整和优化,成功地推动了本领域的进步.本文将全面回顾基于深度学习的SAR图像弱小目标检测,以数据集和方法为研究对象,深入分析SAR弱小目标检测任务所面临的主要挑战,总结最新检测方法的特点和应用场景,并汇总整理了公开数据集与常用性能评估指标.最后,总结本任务的应用现状,并对未来的发展趋势进行展望.

关键词：弱小目标目标检测 SAR图像散射信息目标特性

长江上游保护区干流江安-重庆段禁渔初期鱼类时空分布特点

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水生生物学报 2024年第4期48卷 558-567页

作者：田盼盼李祥艳邓华堂王导群刘绍平陈大庆段辛斌王珂田辉伍中国水产科学研究院长江水产研究所/国家农业科学重庆观测实验站武汉430223 西南大学生命科学学院重庆400715

为掌握“长江十年禁渔”初期长江上游保护区干流江安-重庆江段鱼类资源时空分布特征,研究在开展鱼类资源调查的同时,利用SIMRADEK80分裂波束科研回声探测仪于2020年12月和2021年5月在江安-重庆江段开展水声探测。水声学探测结果表明,江... 详细信息

为掌握“长江十年禁渔”初期长江上游保护区干流江安-重庆江段鱼类资源时空分布特征,研究在开展鱼类资源调查的同时,利用SIMRADEK80分裂波束科研回声探测仪于2020年12月和2021年5月在江安-重庆江段开展水声探测。水声学探测结果表明,江安-重庆江段2020年12月和2021年5月鱼类平均密度分别为25.31和41.23 ind./1000 m^(3),鱼类目标强度均值分别为–55.81和–52.79 dB,无显著差异,估算鱼类平均体长分别为17.97和24.36 cm。在水平方向上,两次调查鱼类都主要分布在重庆-江津江段,两次水声学探测的鱼类密度在垂直方向上呈现出一定差异,2020年12月表现为下层>中层>上层,2021年5月表现为上层>中层>下层。此次鱼类资源调查共发现了鱼类12科62种,其中瓦氏黄颡鱼、光泽黄颡鱼、蒙古鲌和贝氏䱗等小型鱼类的数量占比达到50.21%,与水声学结果一致。研究初步探究了保护区内鱼类在不同时段的空间分布规律,评估了禁捕初期长江上游鱼类分布特征,为长江“十年禁渔”生态效果评估提供基础数据参考。

关键词：鱼类资源水声学时空分布禁渔长江上游保护区

微波预处理对加热卷烟用烤烟烟叶常规化学成分及挥发性香气成分的影响

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轻工学报 2024年第2期39卷 69-79页

作者：田金虎袁颖卢昕博汤晓东潘力王雨凝叶兴乾蒋健浙江大学生物系统工程与食品科学学院浙江杭州310000 浙江中烟工业有限责任公司技术中心浙江杭州310000

以河南产区的下部烤烟样品为原料,采用微波干燥和微波水热两种方法预处理原料,利用连续流动分析、高效液相色谱、气相色谱-离子迁移谱(GC-IMS)等技术对不同微波预处理烤烟烟叶中的常规化学成分及挥发性香气成分进行分析。结果表明:微波... 详细信息

以河南产区的下部烤烟样品为原料,采用微波干燥和微波水热两种方法预处理原料,利用连续流动分析、高效液相色谱、气相色谱-离子迁移谱(GC-IMS)等技术对不同微波预处理烤烟烟叶中的常规化学成分及挥发性香气成分进行分析。结果表明:微波水热处理可降低烤烟烟叶中水溶性糖、还原糖、植物碱及酚类物质含量,提高总氮、石油醚提取物含量,并显著增加烤烟原叶的氮碱比(P≤0.05),其中微波水热700 W-6 min处理组氮碱比高达1.65;而经微波干燥处理后,烤烟烟叶中常规化学成分整体仍处于优质烟叶指标范畴,且挥发碱含量显著增加(P≤0.05),部分预处理组中绿原酸和芸香苷含量增加;此外,GC-IMS共鉴定出56种挥发性香气成分,微波水热处理可增加烤烟的新鲜清香,微波干燥处理则可增加其甜香味。

关键词：微波水热处理微波干燥处理烤烟烟叶加热卷烟挥发性香气成分

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Photometric solution and period analysis of the contact binary system AH Cnc

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Research in Astronomy and Astrophysics 2016年第10期16卷 63-70页

作者： Ying-jiang Peng Zhi-Quan Luo Xiao-Bin Zhang li-Cai Deng Kun Wang jian-feng tian Zheng-Zhou Yan Yang pan Wei-jing Fang Zhong-Wen feng De-lin tang Qi-li liu jin-jiang Sun Qiang Zhou Physics and Space Science College China West Normal University Nanchong 637002 China National Astronomical Observatories Chinese Academy of Sciences Beijing 100012 China Purple Mountain Observatory Chinese Academy of Sciences Nanjing 210008 China School of Physical Electronics University of Electronic Science and Technology of China Chengdu 610054 China

Photometric observations of AH Cnc, a W UMa-type system in the open cluster M67, were car- fled out by using the 50BIN telescope. About 100h of time-series/3- and V-band data were taken, based on which eight new times of light minima were determined. By applying the Wilson-Devinney method, the light curves were modeled and a revised photometric solution of the binary system was derived. We con- firmed that AH Cnc is a deep contact （f = 51%）, low mass-ratio （q - 0.156） system. Adopting the distance modulus derived from study of the host cluster, we have re-calculated the physical parameters of the binary system, namely the masses and radii. The masses and radii of the two components were estimated to be respectively 1.188（4-0.061） Me, 1.332（4-0.063） RQ for the primary component and 0.185（4-0.032） Me, 0.592（4-0.051） Re for the secondary. By adding the newly derived minimum timings to all the available data, the period variations of AH Cnc were studied. This shows that the orbital period of the binary is con- tinuously increasing at a rate of dp/dt = 4.29 x 10-10 d yr-1. In addition to the long-term period increase, a cyclic variation with a period of 35.26 yr was determined, which could be attributed to an unresolved tertiary component of the system.

关键词： methods: data analysis -- astronomical instrumentation -- binaries: eclipsing stars closestars -- Galaxy: open clusters and associations: individual (M67)

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罗浮锥薄木饰面胶合板生产工艺研究

西南林业大学学报（自然科学） 2024年第3期44卷 206-211页

作者：刘衡潘启龙唐继新蒋志林杨桂芳杨丽梅田龙黄胜强中国林业科学研究院热带林业实验中心广西凭祥532600 广西友谊关森林生态系统定位观测研究站广西凭祥532600 崇左凭祥友谊关森林生态系统广西野外科学观测研究站广西凭祥532600

为提升罗浮锥木材的高附加值,以桉木胶合板为基材,基于正交试验设计,研究施胶量与热压工艺参数(温度、时间和压力)对罗浮锥饰面板的含水率、浸渍剥离和表面胶合强度的影响,探明罗浮锥饰面板的优化生产工艺,明确不同类型清漆(硝基清漆、... 详细信息

为提升罗浮锥木材的高附加值,以桉木胶合板为基材,基于正交试验设计,研究施胶量与热压工艺参数(温度、时间和压力)对罗浮锥饰面板的含水率、浸渍剥离和表面胶合强度的影响,探明罗浮锥饰面板的优化生产工艺,明确不同类型清漆(硝基清漆、水性清漆和聚氨酯清漆)涂饰工艺对罗浮锥饰面板的色差和漆膜理化性能的影响。结果表明:罗浮锥饰面板的含水率、浸渍剥离强度及表面胶合强度均符合国标要求,其最佳施胶量为120 g/m^(2),最佳热压温度、热压时间和热压压力分别为160℃、60 s和0.3 MPa;其经硝基清漆涂饰样品的漆膜抗冲击、耐磨、附着力等性能均符合家具表面漆膜理化性能的相关国标要求,经聚氨酯清漆涂饰样品的漆膜抗冲击性不符合家具表面漆膜理化性能相关国标要求,经水性清漆涂饰样品的漆膜耐磨性不符合家具表面漆膜理化性能相关国标要求,但具有最好的附着力和抗冲击性能。罗浮锥木材纹理美观,胶合、热压和涂饰性能优良,作为高端饰面板开发潜力大。

关键词：罗浮锥薄木热压工艺涂饰工艺增值利用