Refereed journal article or data article (A1)

Accretion Disk Parameters Determined from the Great 2015 Flare of OJ 287




List of AuthorsValtonen MJ, Zola S, Pihajoki P, Enestam S, Lehto HJ, Dey L, Gopakumar A, Drozdz M, Ogloza W, Zejmos M, Gupta AC, Pursimo T, Ciprini S, Kidger M, Nilsson K, Berdyugin A, Piirola V, Jermak H, Hudec R, Laine S

PublisherIOP PUBLISHING LTD

Publication year2019

JournalAstrophysical Journal

Journal name in sourceASTROPHYSICAL JOURNAL

Journal acronymASTROPHYS J

Article numberARTN 88

Volume number882

Issue number2

Number of pages8

ISSN0004-637X

eISSN1538-4357

DOIhttp://dx.doi.org/10.3847/1538-4357/ab3573

Self-archived copy’s web addresshttps://research.utu.fi/converis/portal/detail/Publication/42598936


Abstract
In the binary black hole model of OJ. 287, the secondary black hole orbits a much more massive primary, and impacts on the primary accretion disk at predictable times. We update the parameters of the disk, the viscosity, alpha, and the mass accretion rate, <(m)over dot>. We find alpha = 0.26 +/- 0.1 and <(m)over dot> = 0.08 +/- 0.04 in Eddington units. The former value is consistent with Coroniti, and the latter with Marscher & Jorstad. Predictions are made for the 2019 July 30 superflare in OJ. 287. We expect that it will take place simultaneously at the Spitzer infrared channels, as well as in the optical, and that therefore the timing of the flare in optical can be accurately determined from Spitzer observations. We also discuss in detail the light curve of the 2015 flare, and find that the radiating volume has regions where bremsstrahlung dominates, as well as regions that radiate primarily in synchrotron radiation. The former region produces the unpolarized first flare, while the latter region gives rise to a highly polarized second flare.

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Last updated on 2022-07-04 at 16:13