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Kerr-anti-de-sitter/de-sitter black hole in perfect fluid dark matter background

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arXiv 2017年

作者： Xu, Zhaoyi Hou, Xian Wang, Jiancheng Yunnan Observatories Chinese Academy of Sciences 396 Yangfangwang Guandu District Kunming650216 China University of Chinese Academy of Sciences Beijing100049 China Key Laboratory for the Structure and Evolution of Celestial Objects Chinese Academy of Sciences 396 Yangfangwang Guandu District Kunming650216 China Center for Astronomical Mega-Science Chinese Academy of Sciences 20A Datun Road Chaoyang District Beijing100012 China

We obtain the Kerr-anti-de-sitter (Kerr-AdS) and Kerr-de-sitter (Kerr-dS) black hole (BH) solutions to the Einstein field equation in the perfect fluid dark matter background using the Newman-Janis method and Mathematica package. We discuss in detail the black hole properties and obtain the following main results: (i) From the horizon equation grr = 0, we derive the relation between the perfect fluid dark matter parameter α and the cosmological constant Λ when the cosmological horizon rΛ exists. For Λ = 0, we find that α is in the range 0 0 and −7.18M max decreases if α > 0, and αmin increases if α max increases if α > 0 and αmin decreases if α 0 and α 0 while is asymptotically flat only when α is close to zero if α Copyright © 2017, The Authors. All rights reserved.

关键词： Gravitation

The Fourth Catalog of Active Galactic Nuclei Detected by the Fermi Large Area Telescope - Data Release 3

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arXiv 2022年

作者： Ajello, Marco Baldini, Luca Ballet, Jean Bastieri, Denis Gonzalez, Joseff Becerra Bellazzini, Ronaldo Berretta, Alessandra Bissaldi, Elisabetta Bonino, Raffaella Brill, Ari Bruel, Philippe Buson, Sara Caputo, Regina Caraveo, Patrizia A. Cheung, C.C. Chiaro, Graziano Cibrario, Nicolo Ciprini, Stefano Crnogorcevic, Milena Cutini, Sara D’Ammando, Filippo De Gaetano, Salvatore Di Lalla, Niccolo Di Venere, Leonardo Domínguez, Alberto Ramazani, Vandad Fallah Ferrara, Elizabeth C. Fiori, Alessio Fukazawa, Yasushi Funk, Stefan Fusco, Piergiorgio Gammaldi, Viviana Gargano, Fabio Garrappa, Simone Gasparrini, Dario Giglietto, Nico Giordano, Francesco Giroletti, Marcello Green, David Grenier, Isabelle A. Guiriec, Sylvain Horan, Deirdre Hou, Xian Kayanoki, Taishu Kuss, Michael Larsson, Stefan Latronico, Luca Lewis, Tiffany Li, Jian Liodakis, Ioannis Longo, Francesco Loparco, Francesco Lott, Benoit Lovellette, Michael N. Lubrano, Pasquale Madejski, Grzegorz M. Maldera, Simone Manfreda, Alberto Martí-Devesa, Guillem Mazziotta, Mario Nicola Mereu, Isabella Michelson, Peter F. Mirabal, Nestor Mitthumsiri, Warit Mizuno, Tsunefumi Monzani, Maria Elena Morselli, Aldo Moskalenko, Igor V. Negro, Michela Ojha, Roopesh Orienti, Monica Orlando, Elena Ormes, Jonathan F. Pei, Zhiyuan Peña-Herazo, Harold A. Persic, Massimo Pesce-Rollins, Melissa Petrosian, Vahe Pillera, Roberta Poon, Helen Porter, Troy A. Principe, Giacomo Rainò, Silvia Rando, Riccardo Rani, Bindu Razzano, Massimiliano Razzaque, Soebur Reimer, Anita Reimer, Olaf Scotton, Lorenzo Serini, Davide Sgrò, Carmelo Siskind, Eric J. Spandre, Gloria Spinelli, Paolo Suson, Dan J. Tajima, Hiro Torres, Diego F. Valverde, Janeth Yassin, Hend Zaharijas, Gabrijela Department of Physics and Astronomy Clemson University Kinard Lab of Physics ClemsonSC29634-0978 United States Università di Pisa Istituto Nazionale di Fisica Nucleare Sezione di Pisa PisaI-56127 Italy AIM CEA CNRS Université Paris-Saclay Université de Paris Gif-sur-YvetteF-91191 France Istituto Nazionale di Fisica Nucleare Sezione di Padova PadovaI-35131 Italy Dipartimento di Fisica e Astronomia "G. Galilei" Università di Padova Via F. Marzolo 8 PadovaI-35131 Italy Center for Space Studies and Activities "G. Colombo" University of Padova Via Venezia 15 PadovaI-35131 Italy Instituto de Astrofísica de Canarias Observatorio del Teide C/Via Lactea s/n La Laguna TenerifeE-38205 Spain Istituto Nazionale di Fisica Nucleare Sezione di Pisa PisaI-56127 Italy Dipartimento di Fisica Università degli Studi di Perugia PerugiaI-06123 Italy Dipartimento di Fisica "M. Merlin" Università e del Politecnico di Bari via Amendola 173 BariI-70126 Italy Istituto Nazionale di Fisica Nucleare Sezione di Bari BariI-70126 Italy Istituto Nazionale di Fisica Nucleare Sezione di Torino TorinoI-10125 Italy Dipartimento di Fisica Università degli Studi di Torino TorinoI-10125 Italy NASA Postdoctoral Program United States NASA Goddard Space Flight Center GreenbeltMD20771 United States Laboratoire Leprince-Ringuet École polytechnique CNRS IN2P3 PalaiseauF-91128 France Institut für Theoretische Physik and Astrophysik Universität Würzburg WürzburgD-97074 Germany INAF-Istituto di Astrofisica Spaziale e Fisica Cosmica Milano via E. Bassini 15 MilanoI-20133 Italy Space Science Division Naval Research Laboratory WashingtonDC20375-5352 United States Istituto Nazionale di Fisica Nucleare Sezione di Roma "Tor Vergata" RomaI-00133 Italy Space Science Data Center - Agenzia Spaziale Italiana Via del Politecnico snc RomaI-00133 Italy Department of Astronomy University of Maryland College ParkMD20742 United States Istituto Nazionale di Fisica Nucleare Sezio

An incremental version of the fourth catalog of active galactic nuclei (AGNs) detected by the Fermi-Large Area Telescope is presented. This version (4LAC-DR3) derives from the third data release of the 4FGL catalog based on 12 years of E>50 MeV gamma-ray data, where the spectral parameters, spectral energy distributions (SEDs), yearly light curves, and associations have been updated for all sources. The new reported AGNs include 587 blazar candidates and four radio galaxies. We describe the properties of the new sample and outline changes affecting the previously published one. We also introduce two new parameters in this release, namely the peak energy of the SED high-energy component and the corresponding flux. These parameters allow an assessment of the Compton dominance, the ratio of the Inverse-Compton to the synchrotron peak luminosities, without relying on X-ray data. © 2022, CC BY.

关键词： Active Galactic Nuclei

Search for intra-day optical variability in Mrk 501

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arXiv 2017年

作者： Feng, Hai-Cheng Liu, H.T. Fan, X.L. Zhao, Yinghe Bai, J.M. Wang, Fang Xiong, D.R. Li, S.K. Yunnan Observatories Chinese Academy of Sciences 396 Yangfangwang Guandu District Kunming650216 China University of Chinese Academy of Sciences Beijing100049 China Key Laboratory for the Structure and Evolution of Celestial Objects Chinese Academy of Sciences 396 Yangfangwang Guandu District Kunming650216 China Center for Astronomical Mega-Science Chinese Academy of Sciences 20A Datun Road Chaoyang District Beijing100012 China

We present our observations of the optical intra-day variability (IDV) in γ-ray BL Lac object Mrk 501. The observations were run with the 1.02 m and 2.4 m optical telescopes at Yunnan Observatories from 2005 April to 2012 May. The light curve at the R band on 2010 May 15 passes both variability tests (the F test and the ANOVA test). A flare within the light curve on 2010 May 15 has a magnitude change ∆m = 0.03±0.005stat±0.007sys mag, a darkening timescale of τd = 26.7 minutes, and an amplitude of IDV Amp = 2.9%±0.7%. A decline described by 11 consecutive flux measurements within the flare can be fitted linearly with a Pearson’s correlation coefficient r = 0.945 at the confidence level of > 99.99%. Under the assumptions that the IDV is tightly connected to the mass of the black hole, and that the flare duration, being two times τd, is representative of the minimum characteristic timescale, we can derive upper bounds to the mass of the black hole. In the case of the Kerr black hole, the timescale of ∆tobmin = 0.89 hours gives M• . 109.20M☉, which is consistent with measurements reported in the literature. This agreement indicates that the hypothesis about M• and ∆tobmin is consistent with the measurements/data. Copyright © 2017, The Authors. All rights reserved.

关键词： Galaxies

Erratum: 'A Mixture evolution Scenario of the AGN Radio Luminosity Function. II. Do Low- and High-power Radio-loud AGNs Evolve Differently?' (2017, ApJ, 846, 78)

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The Astrophysical Journal 2018年第2期865卷

作者： Zunli Yuan Jiancheng Wang Ming Zhou Longhua Qin Jirong Mao Yunnan Observatories Chinese Academy of Sciences Kunming 650216 People's Republic of China Center for Astronomical Mega-Science Chinese Academy of Sciences Beijing 100012 People's Republic of China Key Laboratory for the Structure and Evolution of Celestial Objects Chinese Academy of Sciences Kunming 650216 People's Republic of China University of Chinese Academy of Sciences Beijing 100049 People's Republic of China

Spectropolarimetry and photometry of the early afterglow of the gamma-ray burst GRB 191221B

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arXiv 2020年

作者： Buckley, David A.H. Bagnulo, S. Britto, R.J. Mao, J. Kann, D.A. Cooper, J. Lipunov, V. Hewitt, D.M. Razzaque, S. Kuin, N.P.M. Monageng, I.M. Covino, S. Jakobsson, P. van der Horst, A.J. Wiersema, K. Böttcher, M. Campana, S. D'Elia, V. Gorbovskoy, E.S. Gorbunov, I. Groenewald, D.N. Hartmann, D.H. Kornilov, V.G. Mundell, C.G. Podesta, R. Thomas, J.K. Tyurina, N. Vlasenko, D. van Soelen, B. Xu, D. South African Astronomical Observatory PO Box 9 Observatory Road Observatory Cape Town7935 South Africa Department of Astronomy University of Cape Town Private Bag X3 Rondebosch7701 South Africa Armagh Observatory & Planetarium College Hill ArmaghBT61 9DG United Kingdom Department of Physics University of the Free State PO Box 339 Bloemfontein9300 South Africa Yunnan Observatories Chinese Academy of Sciences Yunnan Province Kunming650011 China Center for Astronomical Mega-Science Chinese Academy of Sciences 20A Datun Road Chaoyang District Beijing100012 China Key Laboratory for the Structure and Evolution of Celestial Objects Chinese Academy of Sciences Kunming650011 China Glorieta de la Astronomía s/n Granada18008 Spain M. V. Lomonosov Moscow State University SAI Physics Department 13 Univeristetskij pr-t Moscow119991 Russia M.V.Lomonosov Moscow State University Physics Department Leninskie gory GSP-1 Moscow119991 Russia Department of Physics University of Johannesburg PO Box 524 Auckland Park2006 South Africa Mullard Space Science Laboratory Dept. of Space and Climate Sciences University College London Holmbury St Mary DorkingRH5 6NT United Kingdom I-23807 Italy Centre for Astrophysics and Cosmology Science Institute University of Iceland Dunhagi 5 Reykjavík107 Iceland Department of Physics The George Washington University 725 21st St. NW WashingtonDC20052 United States The George Washington University WashingtonDC20052 United States Department of Physics University of Warwick Gibbet Hill Road CoventryCV4 7AL United Kingdom Department of Physics and Astronomy University of Leicester LE1 7RH United Kingdom Centre for Space Research North West University Potchefstroom South Africa ASI-Space Science Data Center via del Politecnico snc Rome00133 Italy INAF - Osservatorio Astronomico di Roma via Frascati 33 Monte Porzio Catone00040 Italy Southern African Large Telescope Foundation PO Box 9 Observatory Road Obse

We report on results of spectropolarimetry of the afterglow of the long gamma-ray burst GRB 191221B, obtained with SALT/RSS and VLT/FORS2, as well as photometry from two telescopes in the MASTER Global Robotic Network, at the MASTER-SAAO (South Africa) and MASTER-OAFA (Argentina) stations. Prompt optical emission was detected by MASTER-SAAO 38 s after the alert, which dimmed from a magnitude (white-light) of ∼ 10 to 16.2 mag over a period of ∼10 ks, followed by a plateau phase lasting ∼10 ks and then a decline to ∼18 mag after 80 ks. The light curve shows complex structure, with four or five distinct breaks in the power-law decline rate. SALT/RSS linear spectropolarimetry of the afterglow began ∼ 2.9 h after the burst, during the early part of the plateau phase of the light curve. Absorption lines seen at ∼ 6010 Å and 5490 Å are identified with the Mg II 2799 Å line from the host galaxy at z = 1.15 and an intervening system located at z = 0.96. The mean linear polarisation measured over 3400 − 8000 Å was ∼1.5% and the mean equatorial position angle (θ) ∼65◦. VLT/FORS2 spectropolarimetry was obtained ∼ 10 h postburst, during a period of slow decline (α = −0.44), and the polarisation was measured to be p = 1.2% and θ = 60◦. Two observations with the MeerKAT radio telescope, taken 30 and 444 days after the GRB trigger, detected radio emission from the host galaxy only. We interpret the light curve and polarisation of this long GRB in terms of a slow-cooling forward-shock. Copyright © 2020, The Authors. All rights reserved.

关键词： Stars

SDSS J012119.10 001949.9:a very short period M dwarf contact binary from SDSS stripe 82

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Research in Astronomy and Astrophysics 2015年第12期15卷 2237-2243页

作者： Lin-Qiao Jiang Sheng-Bang Qian Jia Zhang Yunnan Observatories Chinese Academy of Sciences Key Laboratory of the Structure and Evolution of Celestial Objects Chinese Academy of Sciences University of Chinese Academy of Sciences

We present the first multicolor photometric observations of the short period low-mass eclipsing binary SDSS J012119.10-4301949.9. By using the 2013 version of the Wilson-Devinney code, the photometric solutions are derived. It is found that the system is in a contact configuration （f = 18.9± 6.0%） with a moderate mass ratio of 0.5 ± 0.01. A third light contributing about 6.1± 1.3% of the total luminosity in the V band was found, which may come from a cool tertiary component. The derived high orbital inclination （i - 83.9°± 0.5°） and the almost symmetric three light curves suggest that the determined parameters are reliable. Both the color class and spectral class of the system correspond to a spectral type of M0, which may indicate that SDSS J012119.10-001949.9 belongs to a very rare class of M dwarf contact binaries that are below the theoretical short period limit.

关键词： binaries： eclipsing -- stars： individual （SDSS J012119.10-001949.9） --techniques： photometric

SN 2016X: A type ii-p supernova with a signature of shock breakout from explosion of a massive red supergiant

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arXiv 2018年

作者： Huang, F. Wang, X.-F. Hosseinzadeh, G. Brown, P.J. Mo, J. Zhang, J.-J. Zhang, K.-C. Zhang, T.-M. Howell, D.-A. Arcavi, I. McCully, C. Valenti, S. Rui, L.-M. Song, H. Xiang, D.-F. Li, W.-X. Lin, H. Wang, L.-F. Physics Department and Tsinghua Centre for Astrophysics Tsinghua University Beijing100084 China Department of Astronomy Shanghai Jiao Tong University Shanghai200240 China Key Laboratory for the Structure and Evolution of Celestial Objects Chinese Academy of Sciences Kunming650011 China Department of Physics University of California Santa BarbaraCA93106-9530 United States Las Cumbres Observatory 6740 Cortona Dr. Suite 102 GoletaCA93117-5575 United States George P. and Cynthia Woods Mitchell Institute for Fundamental Physics & Astronomy Texas A&M University Department of Physics Astr Yunnan Observatories Chinese Academy of Sciences Kunming650011 China Centre for Astronomical Mega-Science Chinese Academy of Sciences 20A Datun Road Chaoyang District Beijing100012 China Key Laboratory of Optical Astronomy National Astronomical Observatories Chinese Academy of Sciences Beijing100012 China Department of Physics University of California 1 Shields Avenue DavisCA95616-5270 United States

We present extensive ultraviolet (UV) and optical photometry, as well as dense optical spectroscopy for type II Plateau (IIP) supernova SN 2016X that exploded in the nearby (- 15 Mpc) spiral galaxy UGC 08041. The observations span the period from 2 to 180 days after the explosion;in particular, the Swift UV data probably captured the signature of shock breakout associated with the explosion of SN 2016X. It shows very strong UV emission during the first week after explosion, with contribution of - 20 – 30% to the bolometric luminosity (versus . 15% for normal SNe IIP). Moreover, we found that this supernova has an unusually long rise time of about 12.6 ± 0.5 days in the R band (versus - 7.0 days for typical SNe IIP). The optical light curves and spectral evolution are quite similar to the fast-declining type IIP object SN 2013ej, except that SN 2016X has a relatively brighter tail. Based on the evolution of photospheric temperature as inferred from the Swift data in the early phase, we derive that the progenitor of SN 2016X has a radius of about 930 ± 70 R. This large-size star is expected to be a red supergiant star with an initial mass of & 19 – 20 M based on the mass −− radius relation of the Galactic red supergiants, and it represents one of the most largest and massive progenitors found for SNe IIP. Copyright © 2018, The Authors. All rights reserved.

关键词： Supernovae

A wide star-black-hole binary system from radial-velocity measurements

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arXiv 2019年

作者： Liu, Jifeng Zhang, Haotong Howard, Andrew W. Bai, Zhongrui Lu, Youjun Soria, Roberto Justham, Stephen Li, Xiangdong Zheng, Zheng Wang, Tinggui Belczynski, Krzysztof Casares, Jorge Zhang, Wei Yuan, Hailong Dong, Yiqiao Lei, Yajuan Isaacson, Howard Wang, Song Bai, Yu Shao, Yong Gao, Qing Wang, Yilun Niu, Zexi Cui, Kaiming Zheng, Chuanjie Mu, Xiaoyong Zhang, Lan Wang, Wei Heger, Alexander Qi, Zhaoxiang Liao, Shilong Lattanzi, Mario Gu, Wei-Min Wang, Junfeng Wu, Jianfeng Shao, Lijing Shen, Rongfeng Wang, Xiaofeng Bregman, Joel Stefano, Rosanne Di Liu, Qingzhong Han, Zhanwen Zhang, Tianmeng Wang, Huijuan Ren, Juanjuan Zhang, Junbo Zhang, Jujia Wang, Xiaoli Cabrera-Lavers, Antonio Corradi, Romano Rebolo, Rafael Zhao, Yongheng Zhao, Gang Chu, Yaoquan Cui, Xiangqun Key Laboratory of Optical Astronomy National Astronomical Observatories Chinese Academy of Sciences Beijing China School of Astronomy and Space Sciences University of Chinese Academy of Sciences Beijing China WHU-NAOC Joint Center for Astronomy Wuhan University Wuhan China Department of Astronomy Caltech PasadenaCA United States Sydney Institute for Astronomy School of Physics A28 University of Sydney SydneyNSW Australia The Anton Pannekoek Institute for Astronomy University of Amsterdam Amsterdam Netherlands School of Astronomy and Space Science Nanjing University Nanjing China Misnistry of Education Nanjing China Department of Physics and Astronomy University of Utah Salt Lake CityUT United States CAS Key Laboratory for Research in Galaxies and Cosmology Department of Astronomy University of Science and Technology of China Hefei China Nicolaus Copernicus Astronomical Centre Polish Academy of Sciences Warsaw Poland Instituto de Astrofísica de Canarias La Laguna Tenerife Spain Departamento de Astrofsica Universidad de La Laguna Santa Cruz de Tenerife Spain Astronomy Department University of California BerkeleyCA United States School of Physics and Technology Wuhan University Wuhan China Monash Centre for Astrophysics School of Physics and Astronomy Monash University 19 Rainforest Walk VIC Australia Shanghai Astronomical Observatory Chinese Academy of Sciences Shanghai China INAF–Osservatorio Astrofisico di Torino Pino Torinese Italy Department of Astronomy Xiamen University Xiamen China Kavli Institute for Astronomy and Astrophysics Peking University Beijing China School of Physics and Astronomy Sun Yat-Sen University Zhuhai China Physics Department and Tsinghua Center for Astrophysics Tsinghua University Beijing China Department of Astronomy University of Michigan 1085 South University Street Ann ArborMI United States Harvard-Smithsonian Center for Astrophysics CambridgeMA United States Key Laboratory of Dark Matter and Space Astr

All stellar mass black holes have hitherto been identified by X-rays emitted by gas that is accreting onto the black hole from a companion star. These systems are all binaries with black holes below 30 M*1–4. Theory predicts, however, that X-ray emitting systems form a minority of the total population of star-black hole binaries5,6. When the black hole is not accreting gas, it can be found through radial velocity measurements of the motion of the companion star. Here we report radial velocity measurements of a Galactic star, LB-1, which is a B-type star, taken over two years. We find that the motion of the B-star and an accompanying Hα emission line require the presence of a dark companion with a mass of 68+11−13 M*, which can only be a black hole. The long orbital period of 78.9 days shows that this is a wide binary system. The gravitational wave experiments have detected similarly massive black holes7, 8, but forming such massive ones in a high-metallicity environment would be extremely challenging to current stellar evolution theories9–11. Copyright © 2019, The Authors. All rights reserved.

关键词： Stars

Multi-color light curves and orbital period research of eclipsing binary V1073 Cyg

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arXiv 2017年

作者： Tian, Xiao-man Zhu, Li-ying Qian, Sheng-bang Li, Lin-jia Jiang, Lin-qiao P. O. Box 110 Kunming650216 China Key Laboratory of the Structure and Evolution of Celestial Objects Chinese Academy of Sciences P. O. Box 110 Kunming650216 China University of the Chinese Academy of Science Yuquan Road 19 Sijingshang Block Beijing100049 China School of Physics and Electronic Engineering Sichuan University of Science & Engineering Zigong643000 China

New Multi-color B V Rc Ic photometric observation are presented for W UMa type eclipsing binary V1073 Cyg. The multi-color light curves analysis with the Wilson-Devinney(W-D) procedure acquired the absolute parameters of this system, showing that V1073Cyg is a shallow contact binary system with fill-out factor f = 0.124(±0.011). We collected all available times of light minima spanning 119 years including CCD data to construct the O-C curve and made detailed O-C analysis. The O-C diagram shows that the period change is complex. There exist a long-term continuous decrease and a cyclic variation. The period is decreasing at a rate of P = −1.04(±0.18) × 10−10days · cycle−1, and with the period decrease, V1073 Cyg will evolve to deep contact stage. The cyclic variation with a period of P3 = 82.7(±3.6)years and an amplitude of A = 0.028(±0.002)day may be explained by the magnetic activity of one or both components or the light travel time effect (LTTE) caused by a distant third companion with M3(i′ = 90◦) = 0.511M. Copyright © 2017, The Authors. All rights reserved.

关键词： Stars