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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

SEARCH FOR NEW COSMIC-RAY ACCELERATION SITES WITHIN THE 4FGL CATALOG GALACTIC PLANE SOURCES

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arXiv 2022年

作者： Abdollahi, S. Acero, F. Ackermann, M. Baldini, L. Ballet, J. Barbiellini, G. Bastieri, D. Bellazzini, R. Berenji, B. Berretta, A. Bissaldi, E. Blandford, R.D. Bonino, R. Bruel, P. Buson, S. Cameron, R.A. Caputo, R. Caraveo, P.A. Castro, D. Chiaro, G. Cibrario, N. Ciprini, S. Coronado-Blázquez, J. Crnogorcevic, M. Cutini, S. D'Ammando, F. De Gaetano, S. Di Lalla, N. Dirirsa, F. Di Venere, L. Domínguez, A. Fegan, S.J. Fiori, A. Fleischhack, H. Franckowiak, A. Fukazawa, Y. Fusco, P. Gammaldi, V. Gargano, F. Gasparrini, D. Giacchino, F. Giglietto, N. Giordano, F. Giroletti, M. Glanzman, T. Green, D. Grenier, I.A. Grondin, M.-H. Guiriec, S. Gustafsson, M. Harding, A.K. Hays, E. Hewitt, J.W. Horan, D. Hou, X. Jóhannesson, G. Kayanoki, T. Kerr, M. Kuss, M. Larsson, S. Latronico, L. Lemoine-Goumard, M. Li, J. Longo, F. Loparco, F. Lubrano, P. Maldera, S. Malyshev, D. Manfreda, A. Martí-Devesa, G. Mazziotta, M.N. Mereu, I. Michelson, P.F. Mirabal, N. Mitthumsiri, W. Mizuno, T. Monzani, M.E. Morselli, A. Moskalenko, I.V. Nuss, E. Omodei, N. Orienti, M. Orlando, E. Ormes, J.F. Paneque, D. Pei, Z. Persic, M. Pesce-Rollins, M. Pillera, R. Poon, H. Porter, T.A. Principe, G. Rainò, S. Rando, R. Rani, B. Razzano, M. Razzaque, S. Reimer, A. Reimer, O. Reposeur, T. Sánchez-Conde, M. Parkinson, P.M. Saz Scotton, L. Serini, D. Sgrò, C. Siskind, E.J. Spandre, G. Spinelli, P. Sueoka, K. Suson, D.J. Tajima, H. Tak, D. Thayer, J.B. Torres, D.F. Troja, E. Valverde, J. Wadiasingh, Z. Wood, K. Zaharijas, G. IRAP Université de Toulouse CNRS UPS CNES ToulouseF-31028 France Université Paris Saclay Université Paris Cité CEA CNRS AIM Gif-sur-Yvette F-91191 France Deutsches Elektronen Synchrotron DESY ZeuthenD-15738 Germany Università di Pisa Istituto Nazionale di Fisica Nucleare Sezione di Pisa PisaI-56127 Italy Istituto Nazionale di Fisica Nucleare Sezione di Trieste TriesteI-34127 Italy Dipartimento di Fisica Università di Trieste TriesteI-34127 Italy Istituto Nazionale di Fisica Nucleare Sezione di Padova PadovaI-35131 Italy Dipartimento di Fisica e Astronomia "G. Galilei" Università di Padova PadovaI-35131 Italy Center for Space Studies and Activities "G. Colombo" University of Padova Via Venezia 15 PadovaI-35131 Italy Istituto Nazionale di Fisica Nucleare Sezione di Pisa PisaI-56127 Italy California State University Los Angeles Department of Physics and Astronomy Los AngelesCA90032 United States 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 W. W. Hansen Experimental Physics Laboratory Kavli Institute for Particle Astrophysics and Cosmology Department of Physics SLAC National Accelerator Laboratory Stanford University StanfordCA94305 United States Istituto Nazionale di Fisica Nucleare Sezione di Torino TorinoI-10125 Italy Dipartimento di Fisica Università degli Studi di Torino TorinoI-10125 Italy Laboratoire Leprince-Ringuet École Polytechnique CNRS IN2P3 PalaiseauF-91128 France Institut für Theoretische Physik and Astrophysik Universität Würzburg WürzburgD-97074 Germany NASA Goddard Space Flight Center GreenbeltMD20771 United States INAF-Istituto di Astrofisica Spaziale e Fisica Cosmica Milano via E. Bassini 15 MilanoI-20133 Italy Harvard-Smithsonian Center for Astrophysics CambridgeMA02138 United States Is

Cosmic rays are mostly composed of protons accelerated to relativistic speeds. When those protons encounter interstellar material, they produce neutral pions which in turn decay into gamma rays. This offers a compelling way to identify the acceleration sites of protons. A characteristic hadronic spectrum, with a low-energy break around 200 MeV, was detected in the gamma-ray spectra of four Supernova Remnants (SNRs), IC 443, W44, W49B and W51C, with the Fermi Large Area Telescope. This detection provided direct evidence that cosmic-ray protons are (re-)accelerated in SNRs. Here, we present a comprehensive search for low-energy spectral breaks among 311 4FGL catalog sources located within 5◦ from the Galactic plane. Using 8 years of data from the Fermi Large Area Telescope between 50 MeV and 1 GeV, we find and present the spectral characteristics of 56 sources with a spectral break confirmed by a thorough study of systematic uncertainty. Our population of sources includes 13 SNRs for which the proton-proton interaction is enhanced by the dense target material;the high-mass γ-ray binary LS I +61 303;the colliding wind binary η Carinae;and the Cygnus star-forming region. This analysis better constrains the origin of the γ-ray emission and enlarges our view to potential new cosmic-ray acceleration sites. Copyright © 2022, The Authors. All rights reserved.

关键词： Cosmic rays

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

TESS Cycle 2 observations of roAp stars with 2-min cadence data

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arXiv 2023年

作者： Holdsworth, D.L. Cunha, M.S. Lares-Martiz, M. Kurtz, D.W. Antoci, V. Barceló Forteza, S. De Cat, P. Derekas, A. Kayhan, C. Ozuyar, D. Skarka, M. Hey, D.R. Shi, F. Bowman, D.M. Kobzar, O. Ayala Gómez, A. Bognár, Zs. Buzasi, D.L. Ebadi, M. Fox-Machado, L. García Hernández, A. Ghasemi, H. Guzik, J.A. Handberg, R. Handler, G. Hasanzadeh, A. Jayaraman, R. Khalack, V. Kochukhov, O. Lovekin, C.C. Mikolajczyk, P. Mkrtichian, D. Murphy, S.J. Niemczura, E. Olafsson, B.G. Pascual-Granado, J. Paunzen, E. Posilek, N. Ramón-Ballesta, A. Safari, H. Samadi-Ghadim, A. Smalley, B. Sódor, Á. Stateva, I. Suárez, J.C. Szabó, R. Wu, T. Ziaali, E. Zong, W. Seager, S. Jeremiah Horrocks Institute University of Central Lancashire PrestonPR1 2HE United Kingdom South African Astronomical Observatory P.O. Box 9 Observatory Cape Town7935 South Africa Instituto de Astrofísica e Ciências do Espaço Universidade do Porto CAUP Rua das Estrelas PortoPT4150-762 Portugal Stellar Variability Group Institute of Astrophysics of Andalusia Department of Stellar Physics IAA-CSIC Granada Spain Centre for Space Research North-West University Mahikeng2745 South Africa National Space Institute Technical University of Denmark Elektrovej Kgs. LyngbyDK-2800 Denmark Granada18071 Spain Royal Observatory of Belgium Ringlaan 3 BrusselsB-1180 Belgium ELTE Eötvös Loránd University Gothard Astrophysical Observatory Szent Imre h. u. 112. SzombathelyH-9700 Hungary MTA-ELTE Lendület "Momentum" Milky Way Research Group Hungary HUN-RENSZTE Stellar Astrophysics Research Group Szegedi út Kt. 766 BajaH-6500 Hungary Department of Astronomy and Space Sciences Science Faculty Erciyes University Kayseri Melikgazi38030 Turkey Ankara University Faculty of Science Dept. of Astronomy and Space Sciences Tandogan Ankara06100 Turkey Astronomical Institute of the Czech Academy of Sciences Fričova 298 OndřejovCZ-25165 Czech Republic Department of Theoretical Physics and Astrophysics Masaryk University Kotlářská 2 BrnoCZ-61137 Czech Republic Institute for Astronomy University of Hawaii Honolulu United States Department of Astronomy Peking University Beijing100871 China The Kavli Institute for Astronomy and Astrophysics Peking University Beijing100871 China School of Mathematics Statistics and Physics Newcastle University Newcastle upon TyneNE1 7RU United Kingdom Institute of Astronomy KU Leuven Leuven3001 Belgium Département de Physique et dÁstronomie Université de Moncton MonctonNBE1A 3E9 Canada Virtualmech R&D division Parque Empresarial Nuevo Torneo. Arquitectura 1 Sevilla41015 Spain Konkoly Observatory HUN-REN Research Centre for

We present the results of a systematic search of the Transiting Exoplanet Survey Satellite (TESS) 2-min cadence data for new rapidly oscillating Ap (roAp) stars observed during the Cycle 2 phase of its mission. We find seven new roAp stars previously unreported as such and present the analysis of a further 25 roAp stars that are already known. Three of the new stars show multiperiodic pulsations, while all new members are rotationally variable stars, leading to almost 70 per cent (22) of the roAp stars presented being α2 CVn-type variable stars. We show that targeted observations of known chemically peculiar stars are likely to overlook many new roAp stars, and demonstrate that multi-epoch observations are necessary to see pulsational behaviour changes. We find a lack of roAp stars close to the blue edge of the theoretical roAp instability strip, and reaffirm that mode instability is observed more frequently with precise, space-based observations. In addition to the Cycle 2 observations, we analyse TESS data for all known roAp stars. This amounts to 18 further roAp stars observed by TESS. Finally, we list six known roAp stars that TESS is yet to observe. We deduce that the incidence of roAp stars amongst the Ap star population is just 5.5 per cent, raising fundamental questions about the conditions required to excite pulsations in Ap stars. This work, coupled with our previous work on roAp stars in Cycle 1 observations, presents the most comprehensive, homogeneous study of the roAp stars in the TESS nominal mission, with a collection of 112 confirmed roAp stars in total. © 2023, CC BY.

关键词： Stars

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

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

Stellar and agn feedback in isolated early-type galaxies: The role in regulating star formation and ism properties

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arXiv 2018年

作者： LI, YA-PING YUAN, FENG MO, HOUJUN YOON, DOOSOO GAN, ZHAOMING HO, LUIS C. WANG, BO OSTRIKER, JEREMIAH P. CIOTTI, LUCA Key Laboratory for Research in Galaxies and Cosmology Shanghai Astronomical Observatory Chinese Academy of Sciences 80 Nandan Road Shanghai200030 China School of Astronomy and Space Sciences University of Chinese Academy of Sciences No. 19A Yuquan Road Beijing100049 China Department of Astronomy University of Massachusetts AmherstMA01003-9305 United States Tsinghua Center of Astrophysics and Department of Physics Tsinghua University Beijing100084 China Kavli Institute for Astronomy and Astrophysics Peking University Beijing100871 China Department of Astronomy School of Physics Peking University Beijing100871 China Key Laboratory for the Structure and Evolution of Celestial Objects Yunnan Observatories CAS Kunming650216 China Department of Astronomy Columbia University 550 W 120th Street New YorkNY10027 United States Department of Physics and Astronomy University of Bologna via Piero Gobetti 93/2 Bologna40129 Italy

Understanding how galaxies maintain the inefficiency of star formation with physically self-consistent models is a central problem for galaxy evolution. Although numerous theoretical models have been proposed in recent decades, the debate still exists. By means of high-resolution two-dimensional hydrodynamical simulations, we study the three feedback effects (the stellar wind heating, SNe feedback, and AGN feedback) in suppressing star formation activities on the evolution of early-type galaxies with different stellar masses. AGN feedback models are updated based on Yuan et al. (2018). The gas sources comes exclusively from the mass losses of dying low-mass stars for most of our models. We find that SNe feedback can keep star formation at a significantly low level for low mass elliptical galaxies for a cosmological evolution time. For the high mass galaxies, AGN feedback can efficiently offset the radiative cooling and thus regulate the star formation activities. Such a suppression of star formation is extremely efficient in the inner region of the galaxies. AGB heating cannot account for this suppression for low and high mass galaxies. The X-ray temperature TX and luminosity LX of hot plasma can be in agreement with the observed data with the inclusion of effective feedback processes. These results thus suggest that we can use TX and LX to probe the role of different feedback processes. The inclusion of additional gas sources can make the mass scale between SNe and AGN feedback dominating in suppressing star formation decrease to an observationally inferred value of a few 1010 Mo. Copyright © 2018, The Authors. All rights reserved.

关键词： Galaxies

Insight-Hxmt Observations of The New Black Hole Candidate Maxi J1535-571: Timing Analysis

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arXiv 2018年

作者： Huang, Y. Qu, J.L. Zhang, S.N. Bu, Q.C. Chen, Y.P. Tao, L. Zhang, S. Lu, F.J. Li, T.P. Song, L.M. Xu, Y.P. Cao, X.L. Chen, Y. Liu, C.Z. Chang, H.-K. Yu, W.F. Weng, S.S. Hou, X. Kong, A.K.H. Xie, F.G. Zhang, G.B. Zhou, J.F. Chang, Z. Chen, G. Chen, L. Chen, T.X. Chen, Y.B. Cui, W. Cui, W.W. Deng, J.K. Dong, Y.W. Du, Y.Y. Fu, M.X. Gao, G.H. Gao, H. Gao, M. Ge, M.Y. Gu, Y.D. Guan, J. Gungor, C. Guo, C.C. Han, D.W. Hu, W. Huo, J. Ji, J.F. Jia, S.M. Jiang, L.H. Jiang, W.C. Jin, J. Jin, Y.J. Li, B. Li, C.K. Li, G. Li, M.S. Li, W. Li, X. Li, X.B. Li, X.F. Li, Y.G. Li, Z.J. Li, Z.W. Liang, X.H. Liao, J.Y. Liu, G.Q. Liu, H.W. Liu, S.Z. Liu, X.J. Liu, Y. Liu, Y.N. Lu, B. Lu, X.F. Luo, T. Ma, X. Meng, B. Nang, Y. Nie, J.Y. Ou, G. Sai, N. Shang, R.C. Sun, L. Tan, Y. Tao, W. Tuo, Y.L. Wang, G.F. Wang, H.Y. Wang, J. Wang, W.S. Wang, Y.S. Wen, X.Y. Wu, B.B. Wu, M. Xiao, G.C. Xiong, S.L. Xu, H. Yan, L.L. Yang, J.W. Yang, S. Yang, Y.J. Zhang, A.M. Zhang, C.L. Zhang, C.M. Zhang, F. Zhang, H.M. Zhang, J. Zhang, Q. Zhang, T. Zhang, W. Zhang, W.C. Zhang, W.Z. Zhang, Y. Zhang, Y. Zhang, Y.F. Zhang, Y.J. Zhang, Z. Zhang, Z. Zhang, Z.L. Zhao, H.S. Zhao, J.L. Zhao, X.F. Zheng, S.J. Zhu, Y. Zhu, Y.X. Zou, C.L. Key Laboratory of Particle Astrophysics Institute of High Energy Physics Chinese Academy of Sciences Beijing100049 China University of Chinese Academy of Sciences Chinese Academy of Sciences Beijing100049 China Department of Physics Tsinghua University Beijing100084 China Department of Astronomy Beijing Normal University Beijing100088 China Department of Engineering Physics Tsinghua University Beijing100084 China Institute of Astronomy National Tsing Hua University Hsinchu30013 Taiwan Department of Physics National Tsing Hua University Hsinchu30013 Taiwan Key Laboratory for Research in Galaxies and Cosmology Shanghai Astronomical Observatory Chinese Academy of Sciences Shanghai200030 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 Center for Astronomical Mega-Science Chinese Academy of Sciences Beijing100012 China

We present the X-ray timing results of the new black hole candidate (BHC) MAXI J1535-571 during its 2017 outburst from Hard X-ray Modulation Telescope (Insight-HXMT) observations taken from 2017 September 6 to 23. Following the definitions given by Belloni (2010), we find that the source exhibits state transitions from Low/Hard state (LHS) to Hard Intermediate state (HIMS) and eventually to Soft Intermediate state (SIMS). Quasi-periodic oscillations (QPOs) are found in the intermediate states, which suggest different types of QPOs. With the large effective area of Insight-HXMT at high energies, we are able to present the energy dependence of the QPO amplitude and centroid frequency up to 100 keV which is rarely explored by previous satellites. We also find that the phase lag at the type-C QPOs centroid frequency is negative (soft lags) and strongly correlated with the centroid frequency. By assuming a geometrical origin of type-C QPOs, the source is consistent with being a high inclination system. Copyright © 2018, The Authors. All rights reserved.

关键词： Stars

Kerr-Newman-AdS black hole in quintessential dark energy

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Physical Review D 2017年第6期95卷 064015-064015页

作者： Zhaoyi Xu Jiancheng Wang Yunnan Observatories Chinese Academy of Sciences 396 Yangfangwang Guandu District Kunming 650216 People’s Republic of China University of Chinese Academy of Sciences Beijing 100049 People’s Republic of China Key Laboratory for the Structure and Evolution of Celestial Objects Chinese Academy of Sciences 396 Yangfangwang Guandu District Kunming 650216 People’s Republic of China Center for Astronomical Mega-Science Chinese Academy of Sciences 20A Datun Road Chaoyang District Beijing 100012 People’s Republic of China

Quintessential dark energy with pressure p and density ρ is related by equation of state p=ωρ with the state parameter −1<ω<−1/3. The cosmological dark energy influence on black hole spacetime is interesting and important. In this paper, we study the Kerr-Newman-AdS solutions of the Einstein-Maxwell equation in quintessence field around a black hole by Newman-Janis algorithm and complex computations. From the horizon structure equation, we obtain the expression between quintessence parameter α and cosmological constant Λ if the black hole exists two cosmological horizon rq and rc when ω=−2/3, the result is different from rotational black hole in quintessence matter situation. Through analysis we find that the black hole charge cannot change the value of α. But the black hole spin and cosmological constant are opposite. The black hole spin and cosmological constant make the maximum value of α small. The existence of four horizon leads seven types of extremal black holes to constrain the parameter α. With the state parameter ω ranging from −1 to −1/3, the maximum value of α changes from Λ to 1. When ω→−1, the quintessential dark energy likes cosmological constant. The singularity of the black holes is the same with that of Kerr black hole. We also discuss the rotation velocity of the black holes on the equatorial plane for ω=−2/3, −1/2 and −1/3. For small value of α, the rotation velocity on the equatorial plane is asymptotically flat and it can explain the rotation curves in spiral galaxies.

关键词： Dark energy General relativity