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Timing and Spectral Analysis of the Black Hole X-Ray Binary MAXI J1803-298 with Insight-HXMT Data

Research in Astronomy and Astrophysics 2024年第6期24卷 209-224页

作者： Ying-Chen Xu Jin-Lu Qu MMéndez Rui-Can Ma Long Ji Liang Zhang Yue Huang qing-cui bu Li-Ming Song 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 Kapteyn Astronomical Institute University of GroningenP.O.BOX 8009700 AV GroningenThe Netherlands Dongguan Neutron Science Center Dongguan 523808China School of Physics and Astronomy Sun Yat-Sen UniversityZhuhai 519082China Institut für Astronomie und Astrophysik Kepler Center for Astro and Particle PhysicsEberhard Karls UniversitätSand 1D-72076 TübingenGermany

We present a comprehensive analysis of the 2021 outburst of MAXI J1803–298 utilizing observations of the Insight-Hard X-ray Modulation Telescope(Insight-HXMT)spanning from the low hard state to the high soft *** the Insight-HXMT data set,compared to the previous work,we identify a more prolonged presence of typeC quasi-periodic oscillations(QPOs)with centroid frequencies ranging from~0.16 to 6.3 Hz,which present correlations with the hardness ratio and the photon index of the Comptonized *** QPO frequencies less than~2 Hz,the QPO phase lags are hard(photons of 10–19 keV arrive later than those of 1–4 keV),while at higher frequencies,the lags become soft at and above~4 ***,the spectra in all Insight-HXMT observations consist of a multi-color blackbody component and a Comptonized component,as commonly observed in classical black hole X-ray *** analyze state transitions and the evolution of accretion geometry in this *** fitted inner disk radius increases abnormally during the low hard state,hypothesized to result from the corona condensing onto the inner ***,two significant drops in flux are observed during the soft intermediate state,maybe implying changes in the corona/jet and the disk,respectively.

关键词： X-rays:binaries accretion accretion disks stars:black holes

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Nonlinear Variability Observed with Insight-HXMT in MAXI J1820+070 and MAXI J1535-571

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Research in Astronomy and Astrophysics 2023年第8期23卷 346-354页

作者： Qi Ding Long Ji qing-cui bu Tiekuang Dong Jin Chang Key Laboratory of Dark Matter and Space Astronomy Purple Mountain ObservatoryChinese Academy of SciencesNanjing 210033China School of Astronomy and Space Sciences University of Science and Technology of ChinaHefei 230026China School of Physics and Astronomy Sun Yat-sen UniversityZhuhai 519000China Institut für Astronomie und Astrophysik Kepler Center for Astro and Particle PhysicsEberhard KarlsUniversitätSand 1D-72076 TübingenGermany National Astronomical Observatories Chinese Academy of SciencesBeijing 100101China

We present the timing analysis of the nonlinear variability in two black hole low mass X-ray binaries MAXI J1820+070 and MAXI J1535-571 by using the bicoherence,a measure of phase coupling at different Fourier *** found different patterns,e.g.,“cross”and“hypotenuse,”for LFQPOs in different outburst *** they can be clearly distinguished,bicoherence patterns are similar over a wide energy range of 1–100 *** is intriguing that in some type-C QPOs we found the patterns that are normally observed in type-B *** the contrary,the“hypotenuse”pattern,a characteristic of type-C QPOs,was detected in a type-B *** suggests that different types of QPOs may originate from similar underlying *** addition,we speculate that the nonlinear variability may be a promising approach to disentangle distinct QPO models which assume different interactions between the broadband noise and QPO components.

关键词： black hole physics-instrumentation detectors-methods data analysis-X-rays binaries

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Study on the Performance of the GRANDProto300 Particle Detector Array by Simulation

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Research in Astronomy and Astrophysics 2024年第1期24卷 173-177页

作者： Fu-Lin Dai Quan-bu Gou Xiaoyuan Huang Yi-qing Guo Key Laboratory of Dark Matter and Space Astronomy Purple Mountain ObservatoryChinese Academy of SciencesNanjing 210023China School of Astronomy and Space Science University of Science and Technology of ChinaHefei 230026China Key Laboratory of Particle Astrophysics Institute of High Energy PhysicsChinese Academy of SciencesBeijing 100049China University of Chinese Academy of Sciences Beijing 100049China

The Giant Radio Array for Neutrino Detection(GRAND)is a proposed large-scale observatory designed to detect cosmic rays,gamma-rays,and neutrinos with energies exceeding 100 Pe *** GRANDProto300 experiment is proposed as the early stage of the GRAND project,consisting of a hybrid array of radio antennas and scintillator *** latter,as a mature and traditional detector,is used to cross-check the nature of the candidate events selected from radio *** this study,we developed a simulation software called G4GRANDProto300,based on the Geant4 software package,to optimize the spacing of the scintillator detector array and to investigate its effective *** analysis was conducted at various zenith angles under different detector spacings,including 300,500,600,700,and 900 *** results indicate that,for large zenith angles used to search for cosmic-ray in the GRAND project,the optimized effective area is with a detector spacing of 500 *** G4GRANDProto300 software that we developed could be used to further optimize the layout of the particle detector array in future work.

关键词： astroparticle physics instrumentation:detectors (ISM:)cosmic rays

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Insight-HXMT observations of the Crab pulsar

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Research in Astronomy and Astrophysics 2019年第6期19卷 109-116页

作者： You-Li Tuo Ming-Yu Ge Li-Ming Song Lin-Li Yan qing-cui bu Jin-Lu Qu Key Laboratory of Particle Astrophysics Institute of High Energy Physics Chinese Academy of Sciences Beijing 100049 China University of the Chinese Academy of Sciences Beijing 100049 China School of Mathematics and Physics Anhui Jianzhu University Hefei 230601 China

We report on X-ray emission properties of the Crab pulsar(PSR B0531+21) using observations by Insight-HXMT during its first year after launch. We obtained high signal-to-noise profiles in the X-ray energy band 11–250 keV. We have confirmed an increase in the flux ratio of the second peak over the main peak with increasing energy, consistent with other missions. The separation of the two peaks shows no significant trend with increasing energy. The phase-averaged spectrum, fitted by a logpar model, and the phase-resolved spectra of the Crab pulsar, fitted by a powerlaw in the different energy bands of HXMT, are consistent with RXTE and NuSTAR in that photon indices evolve as a function of phase as well as a function of energy, contributing to a broadband modeling.

关键词： stars neutron star-pulsars individual(Crab)-X-rays

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Microscopic and spectroscopic analysis of atmospheric iron-containing single particles in Lhasa,Tibet

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Journal of Environmental Sciences 2024年第7期141卷 40-50页

作者： Junyu Chen Daobin Zhang Yiran Fu Jinhu Wang Xiaomei cui Ci-ren Qu-zong Qiangying Zhang Chan Jin bu Duo School of Ecology and Environment Tibet UniversityLhasa 850000China Shanghai Institute of Applied Physics Chinese Academy of SciencesShanghai 201800China Institute of Tibetan Plateau Research Chinese Academy of SciencesBeijing 100101China

The Tibetan Plateau,known as the“Third Pole”,is currently in a state of perturbation caused by intensified human *** this study,56 samples were obtained at the five sampling sites in typical area of Lhasa city and their physical and chemical properties were investigated by TEM/EDS,STXM,and NEXAFS *** careful examination of 3387single particles,the results showed that Fe should be one of the most frequent metal *** Fe-containing single particles in irregular shape and micrometer size was about7.8%and might be mainly from local ***,the Fe was located on the subsurface of single particles and might be existed in the form of iron ***,the core-shell structure of iron-containing particles were about 38.8%and might be present as single-,dual-or triple-core shell structure and multi-core shell structure with the Fe/Si ratios of 17.5,10.5,2.9 and 1.2,***,iron and manganese were found to coexist with identical distributions in the single particles,which might induce a synergistic effect between iron and manganese in catalytic ***,the solid spherical structure of Fe-containing particles without an external layer were about 53.4%.The elements of Fe and Mn were co-existed,and might be presented as iron oxide-manganese oxide-silica ***,the ferrous and ferric forms of iron might be *** information can be valuable in expanding our understanding of Fe-containing particles in the Tibetan Plateau atmosphere.

关键词： Fe-containing single particle Irregular shape Core-shell structure Solid spherical structure Transmission electron microscopy Synchrotron X-ray microscopy

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Heterochronous multiple primary prostate cancer and lymphoma:A case report

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World Journal of Clinical Cases 2024年第7期12卷 1333-1338页

作者： Jin-Long Liang Yu-qing bu Li-Li Peng Hong-Zhen Zhang Department of Oncology Hebei General HospitalShijiazhuang 050051Hebei ProvinceChina

BACKGROUND Multiple primary malignant tumors(MPMTs)are rare type of cancer,especially when solid tumors are the first and lymphoma is the second primary *** report a patient with heterochronous MPMTs consisting of prostate cancer and rectal diffuse large B-cell lymphoma(DLBCL).CASE SUMMARY We report a 77-year-old male patient diagnosed with prostate cancer who was treated with radiation therapy and one year of endocrine therapy with bicalutamide(50 mg per day)and an extended-release implant of goserelin(1/28 d).Seven years later,rectal DLBCL with lung metastases was *** Although rare,the possibility of prostate cancer combined with a double primary cancer of DLBCL can provide a deeper understanding.

关键词： Multiple primary malignant tumors Radiation therapy Diffuse large B-cell lymphoma Prostate cancer Non-Hodgkin lymphoma Case report

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A Privacy-preserving Energy Management System Based on Homomorphic Cryptosystem for IoT-enabled Active Distribution Network

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Journal of Modern Power Systems and Clean Energy 2024年第1期12卷 167-178页

作者： Qian Hu Siqi bu Wencong Su Vladimir Terzija the Department of Physics Hong Kong Baptist UniversityHong KongChina the Department of Electrical and Electronic Engineering Shenzhen Research InstituteThe Hong Kong Polytechnic UniversityHong KongChina the Department of Electrical and Computer Engineering University of Michigan-DearbornDearbornMI 48128USA the School of Engineering Newcastle UniversityNewcastleUK

Active distribution network(ADN),as a typically cyber-physical system,develops with the evolution of Internet of Things(IoTs),which makes the network vulnerable to cybersecurity *** this paper,the eavesdropping attacks that lead to privacy breaches are addressed for the IoT-enabled ADN.A privacy-preserving energy management system(EMS)is proposed and empowered by secure data exchange protocols based on the homomorphic *** the information transmission among distributed generators and load customers in the EMS,private information including power usage and electricity bidding price can be effectively protected against eavesdropping *** correctness of the final solutions,e.g.,optimal market clearing price and unified power utilization ratio,can be deterministically *** simulation results demonstrate the effectiveness and the computational efficiency of the proposed homomorphically encrypted EMS.

关键词： Eavesdropping attack energy management system homomorphic cryptosystem Internet of Things(IOTs) active distribution network(ADN) privacy-preserving

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Photocatalytic reduction of CO_(2) with H_(2)O into C_(2)H_(6) mediated by dual metalation strategy

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Science China Chemistry 2024年第5期67卷 1381-1383页

作者： Mei Wang Tong-bu Lu School of Materials Science and Engineering Institute for New Energy Materials&Low Carbon TechnologiesTianjin University of TechnologyTianjin 300384China

Artificial solar-energy-driven CO_(2) reduction into value-added fuels under mild conditions provides a promising strategy to mitigate energy crisis and alleviate environmental issues around the world. Among diverse products of CO_(2) reduction reaction, C_(2+) compounds are more desirable in terms of their high energy density and commercial value [1].Thus far, various photocatalysts have been constructed for CO_(2) reduction.

关键词： reduction desirable value

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Gamma/Hadron Separation Method for the HADAR Experiment

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Research in Astronomy and Astrophysics 2024年第3期24卷 70-74页

作者： Yang-Zhao Ren Tian-Lu Chen You-Liang Feng Dan-Zeng Luo-bu Yi-qing Guo Cheng Liu Qi Gao Mao-Yuan Liu Xiang-Li Qian Ya-Ping Wang Zi-Hao Zhang Xin-Long Li qing-Yuan Hou Heng-Jiao Liu qing-Qian Zhou Shan-Jie Shu The Key Laboratory of Cosmic Rays(Tibet University) Ministry of EducationLhasa 850000China Key Laboratory of Particle Astrophysics Institute of High Energy PhysicsChinese Academy of Sciences University of Chinese Academy of Sciences School of Intelligent Engineering Shandong Management University

Ground-based arrays of imaging atmospheric Cherenkov telescopes(IACTs)are the most sensitiveγ-ray detectors for energies of approximately 100 Ge V and *** such IACT is the High Altitude Detection of Astronomical Radiation(HADAR)experiment,which uses a large aperture refractive water lens system to capture atmospheric Cherenkov photons(i.e.,the imaging atmospheric Cherenkov technique).The telescope array has a low threshold energy and large field of view,and can continuously scan the area of the sky being observed,which is conducive to monitoring and promptly responding to transient *** process ofγ-hadron separation is essential in very-high-energy(>30 Ge V)γ-ray astronomy and is a key factor for the successful utilization of *** this study,Monte Carlo simulations were carried out to model the response of cosmic rays within the HADAR *** analyzing the Hillas parameters and the distance between the event core and the telescope,the distinction between air showers initiated byγ-rays and those initiated by cosmic rays was ***,a Quality Factor was introduced to assess the telescope’s ability to suppress the background and to provide a more effective characterization of its performance.

关键词： astroparticle physics-telescopes-methods data analysis

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Detection of Nonlinear Behavior Induced by Hard Limiting in Voltage Source Converters in Wind Farms Based on Higher-order Spectral Analysis

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Journal of Modern Power Systems and Clean Energy 2024年第2期12卷 630-645页

作者： Zetian Zheng Shaowei Huang Qiangsheng bu Chen Shen Jun Yan State Key Laboratory of Power Systems Department of Electrical EngineeringTsinghua UniversityBeijing 100084China State Grid Jiangsu Electric Power Co. Ltd.Research InstituteNanjingChina

In recent years, sub-synchronous oscillation accidents caused by wind power integration have received extensive attention. The recorded constant-amplitude waveforms can be induced by either linear or nonlinear oscillation mechanisms. Hence, the nonlinear behavior needs to be distinguished prior to choosing the analysis method. Since the 1960s, the higher-order statistics(HOS) theory has become a powerful tool for the detection of nonlinear behavior(DNB) in production quality control wherein it has mainly been applied to mechanical condition monitoring and fault diagnosis. This study focuses on the hard limiters of the voltage source converter(VSC) control systems in the wind farms and attempts to detect the nonlinear behavior caused by bi-or uni-lateral saturation hard limiting using the HOS analysis. First, the conventional describing function is extended to obtain the detailed frequency domain information on the bi-and uni-lateral saturation hard limiting. Furthermore, the bi-and tri-spectra are introduced as the HOS, which are extended into bi-and tri-coherence spectra to eliminate the effects of the linear parts on the harmonic characteristics of hard limiting in the VSC control system, respectively. The effectiveness of the HOS in the DNB and the classification of the hard-limiting types is proven, and its detailed derivation and estimation procedure is presented. Finally, the quadratic and cubic phase coupling in the signals is illustrated, and the performance of the proposed method is evaluated and discussed.

关键词： Bi-coherence spectrum detection of nonlinear behavior hard limiting higher-order statistics tri-coherence spectrum voltage source converter wind farms.

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