检索结果-内蒙古大学图书馆

arXiv 2023年

作者： Yang, Jun Zhao, Xiao-Hong Yan, Zhenyu Wang, Xiangyu Ivy Zhang, Yan-Qiu An, Zheng-Hua Cai, Ce Li, Xin-Qiao Li, Zihan Liu, Jia-Cong Liu, Zi-Ke Ma, Xiang Meng, Yan-Zhi Peng, Wen-Xi Qiao, Rui Shao, Lang Song, Li-Ming Tan, Wen-Jun Wang, Ping Wang, Chen-Wei Wen, Xiang-Yang Xiao, Shuo Xue, Wang-Chen Yang, Yu-Han Yin, Yihan Zhang, Bing Zhang, Fan Zhang, Shuai Zhang, Shuang-Nan Zheng, Chao Zheng, Shi-Jie Xiong, Shao-Lin Zhang, Bin-Bin School of Astronomy and Space Science Nanjing University Nanjing210093 China Key Laboratory of Modern Astronomy and Astrophysics Nanjing University Ministry of Education China Yunnan Observatories Chinese Academy of Sciences Kunming China Center for Astronomical Mega-Science Chinese Academy of Sciences Beijing China Key Laboratory for the Structure and Evolution of Celestial Objects Chinese Academy of Sciences Kunming China Key Laboratory of Particle Astrophysics Institute of High Energy Physics Chinese Academy of Sciences 19B Yuquan Road Beijing100049 China University of Chinese Academy of Sciences Beijing100049 China College of Physics Hebei Key Laboratory of Photophysics Research and Application Hebei Normal University Hebei Shijiazhuang050024 China College of Physics Hebei Normal University Shijiazhuang050024 China Guizhou Provincial Key Laboratory of Radio Astronomy and Data Processing Guizhou Normal University Guiyang550001 China Department of Physics University of Rome "Tor Vergata" via della Ricerca Scientifica 1 RomeI-00133 Italy School of Physics Nanjing University Nanjing210093 China Department of Physics and Astronomy University of Nevada Las Vegas NV89154 United States Purple Mountain Observatory Chinese Academy of Sciences Nanjing210023 China

The brightest Gamma-ray burst, GRB 221009A, has spurred numerous theoretical investigations, with particular attention paid to the origins of ultra-high energy TeV photons during the prompt phase. However, analyzing the mechanism of radiation of photons in the ∼MeV range has been difficult because the high flux causes pile-up and saturation effects in most GRB detectors. In this letter, we present systematic modeling of the time-resolved spectra of the GRB using unsaturated data obtained from Fermi/GBM (precursor) and SATech-01/GECAM-C (main emission and flare). Our approach incorporates the synchrotron radiation model, which assumes an expanding emission region with relativistic speed and a global magnetic field that decays with radius, and successfully fits such a model to the observational data. Our results indicate that the spectra of the burst are fully in accordance with a synchrotron origin from relativistic electrons accelerated at a large emission radius. The lack of thermal emission in the prompt emission spectra supports a Poynting-flux-dominated jet composition. Copyright © 2023, The Authors. All rights reserved.

关键词： Synchrotron radiation

来源：评论

学校读者我要写书评

暂无评论

Comparing the Super-Eddington accretion of SMC X-3 and RX J0209.6-7427 with Swift J0243.6+6124

arXiv

引用

arXiv 2022年

作者： Liu, Jiren Vasilopoulos, Georgios Ge, MingYu Ji, Long Weng, Shan-Shan Zhang, Shuang-Nan Hou, Xian Beijing Planetarium 138 Sizhimenwai Road Beijing100044 China Observatoire astronomique de Strasbourg UMR 7550 StrasbourgF-67000 France Institute of High Energy Physics Chinese Academy of Sciences Beijing100049 China School of Physics and Astronomy Sun Yat-sen University 2 Daxue Road Guangdong Zhuhai519082 China Department of Physics Institute of Theoretical Physics Nanjing Normal University Nanjing210023 China Yunnan Observatories Chinese Academy of Sciences Kunming650216 China Key Laboratory for the Structure and Evolution of Celestial Objects Chinese Academy of Sciences Kunming650216 China

We study the giant outbursts of SMC X-3 and RX J0209.6-7427 to compare their super-Eddington accretion regime with that of Swift J0243.6+6124. The high double-peak profile of SMC X-3 is found to be 0.25 phase offset from that below 2.3 × 1038erg s−1, which is similar to Swift J0243 (happened around 0.9 × 1038erg s−1). The profile of RX J0209 shows a similar 0.25 phase offset between high double-peak and low double-peak around 1.25 × 1038erg s−1. The 0.25 phase offset corresponds to a 90 degree angle change of the emission beam and strongly supports for a transition from a fan beam to a pencil beam. Their critical luminosities imply a surface magnetic field ∼ 4 × 1013 G and 2 × 1013 G for SMC X-3 and RX J0209, respectively, based on the recently measured cyclotron line of Swift J0243. The spin-up rate and luminosity of SMC X-3 follows a relation of ν ∝ L0.94±0.03, while that of RX J0209 follows ν ∝ L1.00±0.03, which are similar to Swift J0243 and consistent with the prediction of a radiation-pressure-dominated (RPD) disk. These results indicate that accretion columns are indeed formed above Eddington luminosity, and the population of ULXPs likely corresponds to X-ray pulsars of highest magnetic field. Copyright © 2022, The Authors. All rights reserved.

关键词： Luminance

来源：评论

学校读者我要写书评

暂无评论

A correction method for the telluric absorptions and application to Lijiang observatory

arXiv

引用

arXiv 2021年

作者： Lu, Kai-Xing Zhang, Zhi-Xiang Huang, Ying-Ke Ren, An-Bing Xu, Liang Feng, Hai-Cheng Xin, Yu-Xin Ding, Xu Yu, Xiao-Guang Bai, Jin-Ming Yunnan Observatories Chinese Academy of Sciences Kunming650011 China Key Laboratory for the Structure and Evolution of Celestial Objects Chinese Academy of Sciences Kunming650011 China Department of Astronomy Xiamen University Xiamen Fujian361005 China Qian Xuesen Laboratory of Space Technology China Academy of Space Technology 104 Youyi Road Haidian District Beijing100094 China Department of Astronomy China West Normal University 1 Shida Road Shunqing District Nanchong637002 China

Observing a telluric standard star for correcting the telluric absorption lines of spectrum will take a significant amount of precious telescope time, especially in the long-term spectral monitoring project. Beyond that, it’s difficult to select a suitable telluric standard star near in both time and airmass to the scientific object. In this paper, we present a method of correcting the telluric absorption lines by combining the advantages of long slit spectroscopy. By rotating the slit, we observed the scientific object and a nearby comparison star in one exposure, so that the spectra of both objects should have the same telluric transmission spectrum. The telluric transmission spectrum was constructed by dividing the observed spectrum of comparison star by its stellar template, and was used to correct the telluric absorption lines of the scientific object. Using the long slit spectrograph of Lijiang 2.4-meter telescope, we designed a long-term spectroscopic observation strategy, and finished a four-year spectroscopic monitoring for a pair of objects (an active galactic nuclei and an non-varying comparison star). We applied this method to correct the telluric absorption lines of the long-term monitored spectra by Lijiang 2.4-meter telescope, and investigated the variation of the telluric absorptions at Lijiang Observatory. We found that the telluric absorption transparency is mainly modulated by the seasonal variability of the relative humidity, airmass and seeing. Using the scatter of the [O III] λ5007 fluxes emitted from the narrow-line region of active galactic nuclei as an indicator, we found that the correction accuracy of the telluric absorption lines is 1%. © 2021, CC BY.

关键词： Stars

来源：评论

学校读者我要写书评

暂无评论

K2 photometry on oscillation mode variability: the new pulsating hot B subdwarf star EPIC 220422705

arXiv

引用

arXiv 2022年

作者： Ma, Xiao-Yu Zong, Weikai Fu, Jian-Ning Reed, M.D. Wang, Jiaxin Charpinet, Stéphane Su, Jie Department of Astronomy Beijing Normal University Beijing100875 China Department of Physics Astronomy and Materials Science Missouri State University 901 S. National SpringfieldMO65897 United States College of Science Chongqing University of Posts and Telecommunications Chongqing 400065 China Institut de Recherche en Astrophysique et Planétologie CNRS Université de Toulouse CNES 14 Avenue Edouard Belin Toulouse31400 France Yunnan Observatories Chinese Academy of Sciences Kunming650216 China Key Laboratory for the Structure and Evolution of Celestial Objects Chinese Academy of Sciences Kunming650216 China

We present analysis of oscillation mode variability in the hot B subdwarf star EPIC 220422705, a new pulsator discovered from ∼ 78 days of K2 photometry. The high-quality light curves provide a detection of 66 significant independent frequencies, from which we identified 9 incomplete potential triplets and 3 quintuplets. Those g- and p-multiplets give rotation periods of ∼ 36 and 29 days in the core and at the surface, respectively, potentially suggesting a slightly differential rotation. We derived a period spacing of 268.5 s and 159.4 s for the sequence of dipole and quadruple modes, respectively. We characterized the precise patterns of amplitude and frequency modulations (AM and FM) of 22 frequencies with high enough amplitude for our science. Many of them exhibit intrinsic and periodic patterns of AM and FM, with periods on a timescale of months as derived by the best fitting and MCMC test. The nonlinear resonant mode interactions could be a natural interpretation for such AMs and FMs after other mechanisms are ruled out. Our results are the first step to build a bridge between mode variability from K2 photometry and nonlinear perturbation theory of stellar oscillation. © 2022, CC BY.

关键词： Photometry

来源：评论

学校读者我要写书评

暂无评论

SN 2022vqz: A Peculiar Subluminous Type Ia Supernova with Prominent Early Excess Emission

arXiv

引用

arXiv 2023年

作者： Xi, Gaobo Wang, Xiaofeng Li, Gaici Liu, Jialian Yan, Shengyu Lin, Weili Zhao, Jieming Filippenko, Alexei V. Zheng, WeiKang Brink, Thomas G. Yang, Y. Ehgamberdiev, Shuhrat A. Mirzaqulov, Davron Reguitti, Andrea Pastorello, Andrea Tomasella, Lina Cai, Yongzhi Zhang, Jujia Li, Zhitong Zhang, Tianmeng Sai, Hanna Chen, Zhihao Liu, Qichun Ma, Xiaoran Xiang, Danfeng Physics Department Tsinghua Center for Astrophysics Tsinghua University Beijing100084 China Beijing Planetarium Beijing Academy of Science and Technology Beijing100044 China Department of Astronomy University of California BerkeleyCA94720-3411 United States Ulugh Beg Astronomical Institute Uzbekistan Academy of Sciences Tashkent100052 Uzbekistan National University of Uzbekistan Tashkent100174 Uzbekistan INAF - Osservatorio Astronomico di Brera Via E. Bianchi 46 LC Merate23807 Italy INAF - Osservatorio Astronomico di Padova Vicolo dell'Osservatorio 5 Padova35122 Italy Yunnan Observatories Chinese Academy of Sciences Kunming650216 China Key Laboratory for the Structure and Evolution of Celestial Objects Chinese Academy of Sciences Kunming650216 China International Centre of Supernovae Yunnan Key Laboratory Kunming650216 China Key Laboratory of Optical Astronomy National Astronomical Observatories Chinese Academy of Sciences Beijing100101 China School of Astronomy and Space Science University of Chinese Academy of Sciences Beijing101408 China

We present extensive photometric and spectroscopic observations of the peculiar Type Ia supernova (SN Ia) 2022vqz. It shares many similarities with the SN 2002es-like Type Ia supernovae (SNe Ia), such as low luminosity (MB,max = -18.11 ± 0.16 mag) and moderate post-peak decline rate (Δm15,B = 1.33 ± 0.11 mag). The nickel mass synthesised in the explosion is estimated as 0.20 ± 0.04 Mo from the bolometric light curve, which is obviously lower than that of normal SNe Ia. SN 2022vqz is also characterised by slowly expanding ejecta, with Si II velocities persisting around 7000 km s-1 since 16 days before peak brightness, unique among all known SNe Ia. While all of these properties imply a lower-energy thermonuclear explosion that should leave a considerable amount of unburnt materials, the absent signature of unburnt carbon in spectra of SN 2022vqz is puzzling. A prominent early peak is clearly detected in the ATLAS c- and o-band light curves and in the ZTF gr-band data within days after the explosion. Possible mechanisms for the early peak are discussed, including the sub-Chandrasekhar-mass double-detonation model and interaction of SN ejecta with circumstellar *** find that both models face some difficulties in replicating all aspects of the observed data. As an alternative, we propose a hybrid C-O-Ne white dwarf as the progenitor of SN 2022vqz;it can simultaneously reconcile the tension between low ejecta velocity and the absence of carbon. We further discuss the diversity of SN 2002es-like objects and their origin in the context of different scenarios. Copyright © 2023, The Authors. All rights reserved.

关键词： Supernovae

来源：评论

学校读者我要写书评

暂无评论

Reverberation Mapping of Two Variable Active Galactic Nuclei: Probing the Distinct Characteristics of the Inner and Outer Broad-line Regions

arXiv

引用

arXiv 2024年

作者： Feng, Hai-Cheng Li, Sha-Sha Bai, J.M. Liu, H.T. Lu, Kai-Xing Pang, Yu-Xuan Sun, Mouyuan Wang, Jian-Guo Xu, Yerong Zhang, Yang-Wei Zhou, Shuying Yunnan Observatories Chinese Academy of Sciences Yunnan Kunming650216 China Key Laboratory for the Structure and Evolution of Celestial Objects Chinese Academy of Sciences Yunnan Kunming650216 China Center for Astronomical Mega-Science Chinese Academy of Sciences 20A Datun Road Chaoyang District Beijing100012 China Key Laboratory of Radio Astronomy and Technology Chinese Academy of Sciences 20A Datun Road Chaoyang District Beijing100101 China Department of Astronomy School of Physic Peking University Beijing100871 China Kavli Institute for Astronomy and Astrophysics Peking University Beijing100871 China Department of Astronomy Xiamen University Fujian Xiamen361005 China INAF - IASF Palermo Via U. La Malfa 153 PalermoI-90146 Italy Department of Astronomy & Physics Saint Mary's University 923 Robie Street HalifaxNSB3H 3C3 Canada South-Western Institute for Astronomy Research Yunnan University Kunming650500 China

Current reverberation mapping (RM) studies primarily focus on single emission lines, particularly the Hβ line, which may not fully reveal the geometry and kinematic properties of the broad-line region (BLR). To overcome this limitation, we conducted multiline RM observations on two highly variable active galactic nuclei (AGNs), KUG 1141+371 and UGC 3374, using the Lijiang 2.4 m telescope. Our goal was to investigate the detailed structure of different regions within the BLR. We measured the time lags of multiple broad emission lines (Hα, Hβ, Hγ, He I, and He II) and found clear evidence of radial ionization stratification in the BLRs of both AGNs. Velocity-resolved RM analysis revealed distinct geometry and kinematics between the inner and outer regions of the BLRs. Assuming that velocity-resolved lags reflect the kinematics of BLR, our observations indicate that: (1) in KUG 1141+371, the inner BLR exhibits outflow signatures, while the outer region is consistent with virialized motion;(2) in UGC 3374, the inner region displays virial motion, while the outer region shows inflow. Furthermore, we detected "breathing" behavior in the outer BLR regions of both AGN, while the inner BLR regions show "anti-breathing", which may be linked to intrinsic BLR properties. We discuss these findings in the context of various BLR formation models, highlighting importance of long-term, multiline RM campaigns in understanding of BLR structure and evolution. Additionally, our results suggest that the observed stratification in BLR geometry and kinematics may contribute to the scatter in black hole mass estimates and the rapid changes in velocity-resolved RM signatures reported in recent studies. © 2024, CC BY.

关键词： Active Galactic Nuclei

来源：评论

学校读者我要写书评

暂无评论

New photometric investigation of the low-mass-ratio contact binary star V1853 Orionis

引用

Research in Astronomy and Astrophysics 2019年第4期19卷 77-88页

作者： Jia-Jia He Sheng-Bang Qian Boonrucksar Soonthornthum Amornrat Aungwerojwit Niang-Ping Liu Thawicharat Sarotsakulchai Yunnan Observatories Chinese Academy of Sciences Key Laboratory of the Structure and Evolution of Celestial Objects Chinese Academy of Sciences Center for Astronomical Mega-Science Chinese Academy of Sciences University of Chinese Academy of Sciences National Astronomical Research Institute of Thailand 191 Siriphanich Bldg.2nd Fl.Huay Kaew Rd.Suthep DistrictMuang Department of Physics Faculty of Science Naresuan University

Four-color charge-coupled device(CCD) light curves in the B, V, Rc and I c bands of the totaleclipsing binary system V1853 Orionis(V1853 Ori) are presented. By comparing our light curves with those published by previous investigators, it is determined that the O'Connell effect on the light curves has disappeared. By analyzing those multi-color light curves with the Wilson-Devinney code(W-D code),it is discovered that V1853 Ori is an A-type intermediate-contact binary with a degree of contact factor of f = 33.3%(3.7%) and a mass ratio of q = 0.1896(0.0013). Combining our 10 newly determined times of light minima together with others published in the literature, the period changes of the system are investigated. We found that the general trend of the observed minus calculated(O-C) curve shows a downward parabolic variation that corresponds to a long-term decrease in the orbital period with a rate of d P/dt =-1.96(0.46)×10^(-7) d yr^(-1). The long-term period decrease could be explained by mass transfer from the more-massive component to the less-massive one. By combining our photometric solutions with data from Gaia DR_2, absolute parameters were derived as M_1 = 1.20 M⊙, M_2 = 0.23 M⊙, R_1 = 1.36 R⊙and R_2 = 0.66 R⊙. The long-term period decrease and intermediate-contact configuration suggest that V1853 Ori will evolve into a high fill-out overcontact binary.

关键词： stars: binaries:close stars:binaries:eclipsing stars:individual(V1853 Ori)

来源：评论

学校读者我要写书评

暂无评论

On the injection of relativistic electrons in the jet of 3C 279

arXiv

引用

arXiv 2020年

作者： Hu, Wen Yan, Dahai Dai, Benzhong Zeng, Wei Hu, Qianglin College of Mathematics and Physics Jinggangshan University Jiangxi Province Jian343009 China Key Laboratory for the Structure and Evolution of Celestial Objects Yunnan Observatory Chinese Academy of Sciences Kunming650011 China Department of Astronomy Key Laboratory of Astroparticle Physics Yunnan Province Yunnan University Kunming650091 China

The acceleration of electrons in 3C 279 is investigated through analyzing the injected electron energy distribution (EED) in a time-dependent synchrotron self-Compton + external Compton emission model. In this model, it is assumed that relativistic electrons are continuously injected into the emission region, and the injected EED [Q′e(γ′)] follows a single power-law form with low- and high-energy cutoffs γmin′ and γmax′, respectively, and the spectral index n, i.e, Q′e(γ′) ∝ γ′−n. This model is applied to 14 quasi-simultaneous spectral energy distributions (SEDs) of 3C 279. The Markov Chain Monte Carlo fitting technique is performed to obtain the best-fitting parameters and the uncertainties on the parameters. The results show that the injected EED is well constrained in each state. The value of n is in the range of 2.5 to 3.8, which is larger than that expected by the classic non-relativistic shock acceleration. However, the large value of n can be explained by the relativistic oblique shock acceleration. The flaring activity seems to be related to an increased acceleration efficiency, reflected in an increased γmin′ and electron injection power. Copyright © 2020, The Authors. All rights reserved.

关键词： Gamma rays

来源：评论

学校读者我要写书评

暂无评论

Long-term evolution of surviving companion stars of Type Iax supernovae

arXiv

引用

arXiv 2020年

作者： Liu, Zheng-Wei Zeng, Yaotian 396 Yangfangwang Guandu District Kunming650216 China Key Laboratory for the Structure and Evolution of Celestial Objects CAS Kunming650216 China Center for Astronomical Mega-Science CAS Beijing100012 China University of Chinese Academy of Science Beijing100012 China

The nature of the progenitors and explosion mechanism of Type Iax supernovae (SNe Iax) remain a mystery. The single-degenerate (SD) systems that involve the incomplete pure deflagration explosions of near-Chandrasekhar-mass white dwarfs (WDs) have recently been proposed for producing SNe Iax, in which non-degenerate companions are expected to survive from SN explosions. In this work we concentrate on the main-sequence (MS) donor SD progenitor systems. By mapping the computed companion models from three-dimensional hydrodynamical simulations of ejecta-companion interaction into a one-dimensional stellar evolution code MESA, we investigate the long-term appearance and observational signatures of surviving MS companions of SNe Iax by tracing their post-impact evolution. Depending on different MS companion models, it is found that the shocked surviving companion stars can significantly expand and evolve to be more luminous (5–500 L☉) for a time-scale of 10–104 yr. Comparing with the late-time light curve of an observed SN Iax (SN 2005hk), it is suggested that surviving MS companions of SNe Iax would expect to be visible about 1000 d after the explosion when SN itself has been faded. Copyright © 2020, The Authors. All rights reserved.

关键词： Explosions

来源：评论

学校读者我要写书评

暂无评论

GABE: Galaxy Assembly with Binary evolution

引用

Research in Astronomy and Astrophysics 2019年第10期19卷 121-137页

作者： Zhen Jiang Jie Wang Liang Gao Feng-Hui Zhang Qi Guo Lan Wang Jun Pan Key Laboratory for Computational Astrophysics National Astronomical Observatories Chinese Academy of Sciences Beijing 100101 China School of Astronomy and Space Science University of Chinese Academy of SciencesBeijing 100049China Institute of Computational Cosmology Department of PhysicsUniversity of DurhamSouth RoadDurham DH1 3LEUK Yunnan Observatories Chinese Academy of SciencesKunming 650011China Key Laboratory for the Structure and Evolution of Celestial Objects Chinese Academy of SciencesKunming 650011 China

We developed a new semi-analytic galaxy formation model: Galaxy Assembly with Binary evolution(GABE). For the first time, we introduce binary evolution into semi-analytic models of galaxy formation by using the Yunnan-Ⅱ stellar population synthesis model, which includes various binary interactions. When implementing our galaxy formation model onto the merger trees extracted from the Millennium simulation, it can reproduce a large body of observational results. We find that in the local universe, the model including binary evolution reduces the luminosity at optical and infrared wavelengths slightly, but it increases the luminosity at ultraviolet wavelengths significantly, especially in FUV band. The resulting luminosity function does not change very much over SDSS optical bands and infrared band, but the predicted colors are bluer, especially when the FUV band is under consideration. The new model allows us to explore the physics of various high energy events related to the remnants of binary stars, such as type Ia supernovae, short gamma-ray bursts and gravitational wave events, and their relation with host galaxies in a cosmological context.

关键词： galaxies formation一galaxies luminosity function, mass function-galaxies stellar content

来源：评论

学校读者我要写书评

暂无评论

建议与咨询留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

时间限定

文献类型

馆藏选择

核心期刊

语言

文献类型

帮助

文字说明：

检索规则说明：

检索范例：

分类表

所选分类

限定检索结果

文献类型

馆藏范围

日期分布

学科分类号

主题

机构

作者

语言

请选择保存的检索档案：

请选择收藏分类：

通借通还

建议与咨询 留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

时间限定

文献类型

馆藏选择

核心期刊

语言

文献类型

帮助

文字说明：

检索规则说明：

检索范例：

分类表

所选分类

限定检索结果

文献类型

馆藏范围

日期分布

学科分类号

主题

机构

作者

语言

请选择保存的检索档案： 新增检索档案 确定 取消

请选择收藏分类： 新增自定义分类 确定 取消

通借通还

建议与咨询留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

请选择保存的检索档案：

请选择收藏分类：