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FAST Observations of an Extremely Active Episode of FRB 20201124A.Ⅱ.Energy Distribution

Research in Astronomy and Astrophysics 2022年第12期22卷 70-80页

作者： Yong-Kun Zhang Pei wang Yi Feng Bing Zhang Di Li Chao-Wei Tsai Chen-Hui Niu rui Luo Ju-Mei Yao Wei-Wei Zhu Jin-Lin Han Ke-Jia Lee De-Jiang Zhou Jia-rui Niu Jin-Chen Jiang Wei-Yang wang Chun-Feng Zhang Heng xu bo-Jun wang Jiang-Wei xu National Astronomical Observatories Chinese Academy of SciencesBeijing 100101China University of chinese academy of sciences Beijing 100049China Research Center for Intelligent Computing Platforms Zhejiang LaboratoryHangzhou 311100China Department of Physics and Astronomy University of NevadaLas VegasNV 89154USA Nevada Center for Astrophysics University of NevadaLas VegasNV 89154USA NAOC-UKZN Computational Astrophysics Centre University of KwaZulu-NatalDurban 4000South Africa CSIRO Space and Astronomy PO Box 76EppingNSW 1710Australia Xinjiang Astronomical Observatory Chinese Academy of SciencesUrumqi 830011China Kavli Institute for Astronomy and Astrophysics Peking UniversityBeijing 100871China Department of Astronomy Peking UniversityBeijing 100871China

We report the properties of more than 800 bursts detected from the repeating fast radio burst(FRB)source FRB20201124A with the Five-hundred-meter Aperture Spherical radio Telescope(FAST)during an extremely active episode on UTC 2021 September 25–28 in a series of four *** this second paper of the series,we study the energy distribution of 881 bursts(defined as significant signals separated by dips down to the noise level)detected in the first four days of our 19 hr observational campaign spanning 17 *** event rate initially increased exponentially but the source activity stopped within 24 hr after the 4th *** detection of 542 bursts in one hour during the fourth day marked the highest event rate detected from one single FRB source so *** bursts have complex structures in the time-frequency *** find a double-peak distribution of the waiting time,which can be modeled with two log-normal functions peaking at 51.22 ms and 10.05 s,*** with the emission from a previous active episode of the source detected with FAST,the second distribution peak time is smaller,suggesting that this peak is defined by the activity level of the *** calculate the isotropic energy of the bursts using both a partial bandwidth and a full bandwidth and find that the energy distribution is not significantly *** find that an exponentially connected broken-power law function can fit the cumulative burst energy distribution well,with the lower and higher-energy indices being-1.22±0.01 and-4.27±0.23,*** a radio radiative efficiency ofη_(r)=10^(-4),the total isotropic energy of the bursts released during the four days when the source was active is already 3.9×10^(46)erg,exceeding~23%of the available magnetar dipolar magnetic *** challenges the magnetar models which invoke an inefficient radio emission(e.g.,synchrotron maser models).

关键词： (stars:)pulsars:general stars:individual(FRB 20201124A) methods:data analysis

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Charge resolution in the isochronous mass spectrometry and the mass of ^(51)Co

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Nuclear science and Techniques 2021年第4期32卷 30-37页

作者： xu Zhou Meng wang Yu-Hu Zhang Hu-Shan xu You-Jin Yuan Jian-Cheng Yang Yu.A.Litvinov S.A.Litvinov bo Mei Xin-Liang Yan Xing xu Peng Shuai Yuan-Ming Xing rui-Jiu Chen Xiang-Cheng Chen Chao-Yi Fu Qi Zeng Ming-Ze Sun Hong-Fu Li Qian wang Tong Bao Min Zhang Min Si Han-Yu Deng Ming-Zheng Liu Ting Liao Jin-Yang Shi Yu-Nan Song Institute of Modern Physics Chinese Academy of SciencesLanzhou 730000China School of Nuclear science and Technology University of Chinese Academy of SciencesBeijing 100049China GSI Helmholtzzentrum fu¨r Schwerionenforschung Planckstraße 164291 DarmstadtGermany Sino-French Institute of Nuclear Engineering and Technology Sun Yat-sen UniversityZhuhai 519082China School of science Xi’an Jiaotong UniversityXi’an 710049China School of Nuclear science and Engineering East China University of TechnologyNanchang 330013China CNRS/IN2P3 IJCLabUniversite´Paris-Saclay91405 OrsayFrance

Isochronous mass spectrometry(IMS)of heavyion storage rings is a powerful tool for the mass measurements of short-lived *** IMS experiments,masses are determined through precision measurements of the revolution times of the ions stored in the ***,the revolution times cannot be resolved for particles with nearly the same mass-to-charge(m/q)*** overcome this limitation and to extract the accurate revolution times for such pairs of ion species with very close m/q ratios,in our early work on particle identification,we analyzed the amplitudes of the timing signals from the detector based on the emission of secondary ***,the previous data analysis method is further improved by considering the signal amplitudes,detection efficiencies,and number of stored ions in the ring.A sensitive Z-dependent parameter is introduced in the data analysis,leading to a better resolution of ^(34)Ar^(18+) and ^(51)Co^(27+) with A/Z=17/*** mean revolution times of ^(34)Ar^(18+) and ^(51)Co^(27+) are deduced,although their time difference is merely 1.8 *** uncorrected,overlapped peak of these ions has a full width at half maximum of 7.7 *** mass excess of ^(51)Co was determined to be-27;332e41T keV,which is in agreement with the previous value of-27;342e48T keV.

关键词： Isochronous mass spectrometry Charge resolution Signal amplitude Micro-channel plate ^(51)Co

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Disaster Risk science:A Geographical Perspective and a Research Framework

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International Journal of Disaster Risk science 2020年第4期11卷 426-440页

作者： Peijun Shi Tao Ye Ying wang Tao Zhou Wei xu Juan Du Jing'ai wang Ning Li Chongfu Huang Lianyou Liu bo Chen Yun Su Weihua Fang Ming wang Xiaobin Hu Jidong Wu Chunyang He Qiang Zhang Qian Ye Carlo Jaeger Norio Okada State Key Laboratory of Earth Surface Processes and Resource Ecology Beijing Normal UniversityBeijing 100875China Key Laboratory of Environmental Change and Natural Disasters Ministry of EducationBeijing Normal UniversityBeijing 100875China academy of Disaster Reduction and Emergency Management Ministry of Emergency Management and Ministry of EducationBeijing 100875China Faculty of Geographical science Beijing Normal UniversityBeijing 100875China academy of Plateau science and Sustainability People's Government of Qinghai Province and Beijing Normal UniversityXining 810016.China Global Climate Forum 10178 BerlinGermany Disaster Prevention Research Institute Kyoto UniversityKyoto 611-0011Japan

In this article,we recall the United Nations’30-year journey in disaster risk reduction strategy and framework,review the latest progress and key scientific and technological questions related to the United Nations disaster risk reduction initiatives,and summarize the framework and contents of disaster risk science *** object of disaster risk science research is the"disaster system"consisting of hazard,the geographical environment,and exposed units,with features of regionality,interconnectedness,coupling,and *** stability,hazard threat,and socioeconomic vulnerability together determine the way that disasters are formed,establish the spatial extent of disaster impact,and generate the scale of *** the formation of a disaster,a conducive environment is the prerequisite,a hazard is the necessary condition,and socioeconomic exposure is the sufficient *** geographical environment affects local hazard intensity and therefore can change the pattern of loss *** multi-hazard,disaster chain,and disaster compound could induce complex impacts,amplifying or attenuating hazard intensity and changing the scope of affected *** the light of research progress,particularly in the context of china,we propose a threelayer disaster risk science disciplinary structure,which contains three pillars(disaster science,disaster technology,and disaster governance),nine core areas,and 27 research *** on these elements,we discuss the frontiers in disaster risk science research.

关键词： Disaster system Disaster science Disaster technology Disaster governance Research framework Research frontiers

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Research on dynamic response characteristics of CFRP/Al HC SPs subjected to high-velocity impact

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Defence Technology（防务技术） 2018年第5期14卷 503-512页

作者： Guo-wen Gao En-ling Tang Min-hui Feng Ya-fei Han Yue Li Mei Liu Ying-liang xu Li wang Xiao-chu Lin rui-zhi wang Yi-guang Cheng Liang-liang Zhao Zhi-qiang Liang Jun-ru wang Guan-jie Zhao Qing Gao Tian-zhi Zheng School of Equipment Engineering Shenyang Ligong University

CFRP/Al HC SPs(Carbon Fiber Reinforced Plastic/Aluminum Honeycomb Sandwich Panels)composite structures are widely used in the aerospace and many other fields due to their excellent performances. In order to reveal profoundly the dynamic response characteristics of CFRP/Al HC SPs composite structure under high-velocity impact loading, the experiments about aluminum honeycomb core and CFRP/Al HC SPs composite structure impacted by high-velocity projectiles have been performed by using a one-stage light gas gun loading and a high-speed camera systems, respectively. The whole physical process of collision is analyzed by using TEMA software which is provided by high-speed camera's manufacturer,and the pictures and related physical parameters of the projectile passing through the different layers at the key moments are extracted based on the set frame rate of the video. Meanwhile, the ABAQUS/Explicit module was used to conduct numerical simulation under the same conditions as the experiments, and extracting the pictures and related physical parameters during the projectile penetrating through aluminum honeycomb core and the sandwich panels at the different key moments. The results show that the durations of action for the projectile impacting the Al HC core and the CFRP/Al HC SPs at the velocity about 280 m/s were 86 μs and 240 μs in experiments, respectively, and the durations of action were 90.7μs and 236.2 μs at the same experimental conditions in numerical simulation, which were basically consistent comparing the experimental to simulated results. Moreover, more than 70% for the kinetic energy of the projectile consumed by the sandwich panels was attributed to the front panel and the aluminum honeycomb core during the entire impact process, and all these have verified the reliability of the numerical simulation.

关键词： ABAQUS/Explicit Duration of action between projectile and target Energy absorption

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Cenozoic Vertical-Axis Rotations of the Hoh Xil Basin, Central–Northern Tibet

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Acta Geologica Sinica(English Edition) 2016年第3期90卷 858-869页

作者： RAN bo ZHAO Xixi LIU Zhifei wang Chengshan ZHU Lidong JIN Wei LI Yalin State Key Laboratory of Oil and Gas Reservoir Geology and Exploitation Chengdu University of TechnologyChengdu 610059China State Key Laboratory of Marine Geology Tongji UniversityShanghai 200092China Department of Earth and Planetary sciences University of CaliforniaSanta CruzCA 95064USA State Key Laboratory of Biogeology and Environmental Geology China University of GeosciencesBeijing 100083China Exploration and Development Research Institute of Daqing Oilfield Company Ltd. Daqing 163712China

Understanding the Cenozoic vertical-axis rotation in the Tibetan Plateau is crucial for continental dynamic evolution. Paleomagnetic and rock magnetic investigations were carried out for the Oligocene and Miocene continental rocks of the Hoh Xii basin in order to better understand the tectonic rotations of central Tibet. The study area was located in the Tongtianhe area located in the southern part of the Hoh Xil basin and northern margin of the Tanggula thrust system in central-northern Tibet. A total of 160 independently oriented paleomagnetic samples were drilled from the Tongtianhe section for this study. The magnetic properties of magnetite and hematite have been recognized by measurements of magnetic susceptibility vs. temperature curves and unbiocking temperatures. The mean directions of the Oligocene Yaxicuo Group in stratigraphic coordinates （Declination/Inclination = 354.9°/29.3°, k = 33.0, a9s = 13.5°, N =5 Sites） and of the Miocene Wudaoliang Group in stratigraphic coordinates （Declination/Inclination = 3.60/36.4°, k = 161.0, a9s = 9.7°, N =3 Sites） pass reversal tests, indicating the primary nature of the characteristic magnetizations. Our results suggested that the sampled areas in the Tuotuohe depression of the Hoh Xil basin have undergone no paleomagnetically detectable rotations under single thrusting from the Tanggula thrust system. Our findings, together with constraints from other tectonic characteristics reported by previous paleomagnetic studies, suggest tectonic rotations in the Cuoredejia and Wudaoliang depressions of the Hoh Xil basin were affected by strike-slip faulting of the Fenghuo Shan-Nangqian thrust systems. A closer examination of geological data and different vertical-axis rotation magnitudes suggest the tectonic history of the Hoh Xil basin may be controlled by thrust and strike-slip faulting since the Eocene.

关键词： Tibetan Plateau Hoh xu basin Vertical-axis rotation Cenozoic

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Primary yields of protons measured using CR-39 in laser-induceddeuteron–deuteron fusion reactions

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Nuclear science and Techniques 2020年第6期31卷 90-98页

作者： Yue Zhang Long-Xiang Liu Hong-Wei wang Yu-Gang Ma Bai-Fei Shen Guo-Qiang Zhang Mei-Rong Huang Aldo bonasera Wen-Peng wang Jian-Cai xu Shun Li Gong-Tao Fan Xi-Guang Cao Yong Yu Jian-Jun He Chang-bo Fu Suyalatu Zhang Xin-Rong Hu Xin-Xiang Li Zi-rui Hao Jun-Wen wang Han xue Hai-Juan Fu Shanghai Institute of Applied Physics CASShanghai 201800China University of chinese academy of sciences Beijing 100049China Shanghai Advanced Research Institute CASShanghai 201210China Key Laboratory of Nuclear Physics and Ion-Beam Application(MOE) Institute of Modern PhysicsFudan UniversityShanghai 200433China State Key Laboratory of High Field Laser Physics Shanghai Institute of Optics and Fine MechanicsCASShanghai 201800China Department of Physics Shanghai Normal UniversityShanghai 200234China CAS Center for Excellence in Ultra-Intense Laser science Shanghai 201800China College of Physics and Electronics Information Inner Mongolia University for NationalitiesTongliao 028000China Cyclotron Institute Texas A&M UniversityCollege StationTX 77843USA Laboratori Nazionali del Sud INFNVia Santa Sofia6295123 CataniaItaly Key Laboratory of Beam Technology of Ministry of Education College of Nuclear Science and TechnologyBeijing Normal UniversityBeijing 100875China ShanghaiTech University Shanghai 201210China Shanghai University Shanghai 200444China

Investigating deuteron–deuteron(DD)fusion reactions in a plasma environment similar to the early stages of the Big Bang is an important topic in nuclear *** this study,we experimentally investigated such reactions,using eight laser beams with the third harmonic impacting on a deuterated polyethylene target at the ShenGuang-II Upgrade laser *** work focused on the application of range-filter(RF)spectrometers,assembled from a 70 lm aluminum filter and two CR-39 nuclear track detectors,to measure the yields of primary *** on the track diameter calibration results of 3 MeV protons used to diagnose the tracks on the RF spectrometers,an approximate primary DD-proton yield of(8.5±1.7)×10^6 was obtained,consistent with the yields from similar laser facilities *** indicates that the RF spectrometer is an effective way to measure primary ***,due to the low yields of D^3He-protons and its small track diameter,CR-39 detectors were unable to distinguish it from the background *** other accurate detectors may help to measure these rare events.

关键词： Deuteron-deuteron fusion CR-39 Rangefilter spectrometer DD-proton

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Insight-HXMT on-orbit thermal control status and thermal deformation impact analysis

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Radiation Detection Technology and Methods 2023年第3期7卷 337-349页

作者： Ai-Mei Zhang Yi-Fan Zhang Jin-Yuan Liao Yu-Peng xu Yu-Sa wang Wen-bo Luo Yu-Peng Zhou Zhi-Ying Qian Xiao-bo Li Fang-Jun Lu Shuang-Nan Zhang Li-Ming Song Cong-Zhan Liu Fan Zhang Jian-Yin Nie Juan wang Sheng Yang Tong Zhang Xiao-Jing Liu rui-Jie wang xu-Fang Li Yi-Fei Zhang Zheng-Wei Li xue-Feng Lu He xu Di Wu 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 Spacecraft System Engineering CASTBeijing 100094China

Purpose The Hard X-ray Modulation Telescope is china’s first X-ray astronomy satellite launched on June 15,2017,dubbed *** and passive thermal control measures are employed to keep devices at suitable *** this paper,we analyzed the on-orbit thermal monitoring data of the first 5 years and investigated the effect of thermal deformation on the point spread function(PSF)of the *** We examined the data of the on-orbit temperatures measured using 157 thermistors placed on the collimators,detectors and their support structures and compared the results with the thermal control *** thermal deformation was evaluated by the relative orientation of the two star sensors installed on the main support *** effect was estimated with evolution of the PSF obtained with calibration scanning observations of the Crab *** The on-orbit temperatures met the thermal control requirements thus far,and the effect of thermal deformation on the PSF was negligible after the on-orbit pointing calibration.

关键词： X-ray Insight-HXMT Thermal control Temperature Star sensor data Pointing PSF

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Possible collective band in neutron-rich^(119)Sn

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chinese Physics C 2022年第9期46卷 180-184页

作者： Da-Peng Sun Hong-Fei Bai Wen-Zheng xu Shou-Yu wang Xiao-Guang Wu Hui Jia Chen Liu Bin Qi Guang-Sheng Li Yun Zheng Cong-bo Li Zhi-Quan Li Shuo wang Lin Mu Nai-bo Zhang rui-Ju Guo Aman Rohilla Shandong Provincial Key Laboratory of Optical Astronomy and Solar-Terrestrial Environment School of Space Science and PhysicsInstitute of Space SciencesShandong UniversityWeihai 264209China china Institute of Atomic Energy Beijing 102413China

Excited states of^(119)Sn have been studied using an in-beamγ-ray spectroscopic technique following the incomplete fusion of 7 Li on a^(116)Cd target at a beam energy of 42 MeV.A new bandlike structure is proposed to result from deformed two-particle-two-hole(2p-2h)proton excitations across the Z=50 closed shell based on the systematics of odd-A Sn isotopes and configuration-fixed constrained triaxial relativistic mean-field *** observation extends the boundaries of the deformed 2p-2h collective band to A=119 in Sn isotopes.

关键词： excited state collective band shape coexistence

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Evaluation of human epidermal growth factor receptor 2 in breast cancer with a novel specific aptamer

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Cellular & Molecular Immunology 2017年第4期14卷 398-400页

作者： Ming Chu Jia-rui Kang Wei wang Haichao Li Jia-hui Feng Zheng-yun Chu Ming-bo Zhang Lan xu Yue-dan wang Department of Immunology School of Basic Medical Sciences Peking University Beijing 100191 China Key Laboratory of Medical Immu- nology Ministry of Health Beijing 100191 China Department of Pathology The First Affiliated Hospital of General Hospital of Chinese People's Liberation Army Beijing 100048 China Institute of Microelectronics Peking University Beijing 100871 China National Key Laboratory of science and Technology on Micro/Nano Fabrication Beijing 100871 China peking University First Hospital Peking University Beijing 100034 China pharmacy Departments Liao Ning University of Traditional Chinese Medicine LiaoNing 116600 China

Human epidermal growth factor receptor 2 （HER2）, also known as Neu, ErbB-2, CD340 or p185, plays a significant role in the devdopment and progression of certain aggressive types of breast cancer. Recently, HER2 has ... 详细信息

关键词：核酸类基因 erbB-2 评价研究乳腺肿瘤受体 erbB-2 受体表皮生长因子原癌基因人类

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FAST Observations of an Extremely Active Episode of FRB 20201124A.Ⅳ.Spin Period Search

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Research in Astronomy and Astrophysics 2022年第12期22卷 99-122页

作者： Jia-rui Niu Wei-Wei Zhu Bing Zhang Mao Yuan De-Jiang Zhou Yong-Kun Zhang Jin-Chen Jiang J.L.Han Di Li Ke-Jia Lee Pei wang Yi Feng Dong-Zi Li rui Luo Fa-Yin wang Zi-Gao Dai Chen-Chen Miao Chen-Hui Niu Heng xu Chun-Feng Zhang Wei-Yang wang bo-Jun wang Jiang-Wei xu National Astronomical Observatories Chinese Academy of SciencesBeijing 100101China University of chinese academy of sciences Beijing 100049China Institute for Frontier in Astronomy and Astrophysics Beijing Normal UniversityBeijing 102206China Department of Physics and Astronomy University of NevadaLas VegasNV 89154USA Department of Astronomy Peking UniversityBeijing 100871China NAOC-UKZN Computational Astrophysics Centre University of KwaZulu-NatalDurban 4000South Africa Kavli Institute for Astronomy and Astrophysics Peking UniversityBeijing 100871China Research Center for Intelligent Computing Platforms Zhejiang LaboratoryHangzhou 311100China Cahill Center for Astronomy and Astrophysics MC 249-17 California Institute of TechnologyPasadena CA 91125USA CSIRO Space and Astronomy PO Box 76EppingNSW 1710Australia School of Astronomy and Space science Nanjing UniversityNanjing 210093China Key Laboratory of Modern Astronomy and Astrophysics Nanjing UniversityMinistry of EducationNanjing 210093China Department of Astronomy University of Science and Technology of ChinaHefei 230026China

We report the properties of more than 800 bursts detected from the repeating fast radio burst(FRB)source FRB 20201124A with the Five-hundred-meter Aperture Spherical radio Telescope during an extremely active episode on UTC 2021 September 25th-28th in a series of four *** this fourth paper of the series,we present a systematic search of the spin period and linear acceleration of the source object from both 996 individual pulse peaks and the dedispersed time *** credible spin period was found from this data *** rule out the presence of significant periodicity in the range between 1 ms and 100 s with a pulse duty cycle49±0.08(when the profile is defined by a von-Mises function,not a boxcar function)and linear acceleration up to 300 m s^(-2)in each of the four one-hour observing sessions,and up to 0.6 m s^(-2)in all 4 *** searches contest theoretical scenarios involving a 1 ms–100 s isolated magnetar/pulsar with surface magnetic field10 *** also perform a periodicity search of the fine structures and identify 53 unrelated millisecond-timescale“periods”in multicomponents with the highest significance of 3.9σ.The“periods”recovered from the fine structures are neither consistent nor harmonically *** they are not likely to come from a spin *** caution against claiming spin periodicity with significance below~4σwith multi-components from one-off *** discuss the implications of our results and the possible connections between FRB multi-components and pulsar microstructures.

关键词： pulsars:general methods:observational radio continuum:general

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