X-ray spectral components of the blazar and binary black hole candidate OJ 287 (2005–2020)

Autor: Michael A. Nowak, Kazuhiro Hada, Lankeswar Dey, Daryl Haggard, J. Neilsen, Stefano Ciprini, S. Komossa, Dirk Grupe, Michael Parker, Mauri Valtonen, S. Chandra, S. G. Jorstad, José L. Gómez, Sera Markoff, Achamveedu Gopakumar
Přispěvatelé: Ministerio de Economía y Competitividad (España), Ministerio de Ciencia, Innovación y Universidades (España), European Commission, Junta de Andalucía, National Aeronautics and Space Administration (US), Consejo Superior de Investigaciones Científicas (España), High Energy Astrophys. & Astropart. Phys (API, FNWI)
Rok vydání: 2021
Předmět:
Swift
active [Galaxies]
Astrophysics::High Energy Astrophysical Phenomena
Center of excellence
individual: OJ 287 [Quasars]
FOS: Physical sciences
Library science
Astrophysics::Cosmology and Extragalactic Astrophysics
01 natural sciences
0103 physical sciences
Analysis software
010303 astronomy & astrophysics
Astrophysics::Galaxy Astrophysics
Data archive
Galaxies: nuclei
computer.programming_language
High Energy Astrophysical Phenomena (astro-ph.HE)
Physics
010308 nuclear & particles physics
Member states
Quasars: individual: OJ 287
Astronomy and Astrophysics
Galaxies: active
Astrophysics - Astrophysics of Galaxies
galaxies [X-rays]
X-rays: galaxies
State agency
Galaxies: jets
13. Climate action
Space and Planetary Science
nuclei [Galaxies]
Astrophysics of Galaxies (astro-ph.GA)
jets [Galaxies]
Space Science
Astrophysics - High Energy Astrophysical Phenomena
computer
Zdroj: Digital.CSIC. Repositorio Institucional del CSIC
instname
Monthly Notices of the Royal Astronomical Society, 504(4), 5575-5587. Oxford University Press
ISSN: 1365-2966
0035-8711
Popis: We present a comprehensive analysis of all XMM–Newton spectra of OJ 287 spanning 15 yr of X-ray spectroscopy of this bright blazar. We also report the latest results from our dedicated Swift UVOT and XRT monitoring of OJ 287, which started in 2015, along with all earlier public Swift data since 2005. During this time interval, OJ 287 was caught in extreme minima and outburst states. Its X-ray spectrum is highly variable and encompasses all states seen in blazars from very flat to exceptionally steep. The spectrum can be decomposed into three spectral components: Inverse Compton (IC) emission dominant at low-state, supersoft synchrotron emission that becomes increasingly dominant as OJ 287 brightens, and an intermediately-soft (Γx = 2.2) additional component seen at outburst. This last component extends beyond 10 keV and plausibly represents either a second synchrotron/IC component and/or a temporary disc corona of the primary supermassive black hole (SMBH). Our 2018 XMM–Newton observation, quasi-simultaneous with the Event Horizon Telescope observation of OJ 287, is well described by a two-component model with a hard IC component of Γx = 1.5 and a soft synchrotron component. Low-state spectra limit any long-lived accretion disc/corona contribution in X-rays to a very low value of Lx/LEdd < 5.6 × 10−4 (for MBH, primary = 1.8 × 1010 M⊙). Some implications for the binary SMBH model of OJ 287 are discussed. © 2021 The Author(s).
We would like to thank the Swift and XMM–Newton teams for carrying out our observations and our anonymous referee for their useful comments and suggestions. JLG acknowledges financial support from the Spanish Ministerio de Economía y Competitividad (grants AYA2016-80889-P, PID2019-108995GB-C21), the Consejería de Economía, Conocimiento, Empresas y Universidad of the Junta de Andalucía (grant P18-FR-1769), the Consejo Superior de Investigaciones Científicas (grant 2019AEP112), and the State Agency for Research of the Spanish MCIU through the Center of Excellence Severo Ochoa award for the Instituto de Astrofísica de Andalucía (SEV-2017-0709). SGJ acknowledges financial support from NASA Fermi GI grants 80NSSC20K1565 and 80NSSC20K1566. DH acknowledges funding from the Natural Sciences and Engineering Research Council of Canada (NSERC) and the Canada Research Chairs (CRC) program. We acknowledge the use of data we have obtained with the Neil Gehrels Swift mission. We also acknowledge the use of public data from the Swift data archive. This work made use of data supplied by the UK Swift Science Data Centre at the University of Leicester. This research is partly based on observations obtained with XMM–Newton, an ESA science mission with instruments and contributions directly funded by ESA Member States and NASA. This research has made use of the XRT Data Analysis Software (XRTDAS) developed under the responsibility of the ASI Space Science Data Center (SSDC), Italy.
Databáze: OpenAIRE
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