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OJ287 is a quasi-periodic quasar with roughly 12 year optical cycles. It displays prominent outbursts which are predictable in a binary black hole model. The model predicted a major optical outburst in December 2015. We found that the…

We model the binary black hole system OJ287 as a spinning primary and a non-spinning secondary. It is assumed that the primary has an accretion disk which is impacted by the secondary at specific times. These times are identified as major…

Cosmology and Nongalactic Astrophysics · Physics 2015-05-14 M. Valtonen , S. Mikkola , H. J. Lehto , T. Hyvönen , K. Nilsson , D. Merritt , A. Gopakumar , H. Rampadarath , R. Hudec , M. Basta , R. Saunders

OJ 287 is the best-known supermassive black hole binary candidate in the nanohertz gravitational wave band. It exhibits periodic flares every $\sim$ 12 years, likely caused by collisions of a smaller-mass secondary with the accretion disk…

High Energy Astrophysical Phenomena · Physics 2025-09-24 Sean M. Ressler , Luciano Combi , Bart Ripperda , Xinyu Li

The compact binary system in OJ287 is modelled to contain a spinning primary black hole with an accretion disk and a non-spinning secondary black hole. Using Post Newtonian (PN) accurate equations that include 2.5PN accurate non-spinning…

High Energy Astrophysical Phenomena · Physics 2014-11-20 M. J. Valtonen , S. Mikkola , D. Merritt , A. Gopakumar , H. J. Lehto , T. Hyvönen , H. Rampadarath , R. Saunders , M. Basta , R. Hudec

OJ 287 is a blazar thought to be a binary system containing a ~ 18 billion solar mass primary black hole accompanied by a ~ 150 million solar mass secondary black hole in an eccentric orbit, which triggers electromagnetic flares twice in…

High Energy Physics - Phenomenology · Physics 2023-05-31 Ahmad Alachkar , John Ellis , Malcolm Fairbairn

Tests of Einstein's general theory of relativity have mostly been carried out in weak gravitational fields where the space-time curvature effects are first-order deviations from Newton's theory. Binary pulsars provide a means of probing the…

Results from regular monitoring of relativistic compact binaries like PSR 1913+16 are consistent with the dominant (quadrupole) order emission of gravitational waves (GWs). We show that observations associated with the binary black hole…

High Energy Astrophysical Phenomena · Physics 2019-08-14 Lankeswar Dey , M. J. Valtonen , A. Gopakumar , S. Zola , R. Hudec , P. Pihajoki , S. Ciprini , A. V. Filippenko

The highly variable blazar OJ~287 is commonly discussed as an example of a binary black hole system. The 130 year long optical light curve is well explained by a model where the central body is a massive black hole of 18.35$\times$10$^9$…

Light curves for more than century optical photometric observations of the blazar OJ 287 reveals strong flares with a quasi-period of about 12 years. For a long time, this period has been interpreted by processes in a binary black hole…

High Energy Astrophysical Phenomena · Physics 2021-03-26 M. S. Butuzova , A. B. Pushkarev

The supermassive short period black hole binary OJ287 is discussed as a new precision testing ground for general relativity and alternate gravity theories. Like in the case of binary pulsars, the relativistic gravity effects are…

Astrophysics · Physics 2008-03-17 C. Sivaram

We examine the ability to test the black hole no-hair theorem at the 10% level in this decade using the binary black hole in OJ287. In the test we constrain the value of the dimensionless parameter q that relates the scaled quadrupole…

Cosmology and Nongalactic Astrophysics · Physics 2015-05-30 M. J. Valtonen , S. Mikkola , H. J. Lehto , A. Gopakumar , R. Hudec , J. Polednikova

We study the dynamics of a pair of extremal (half-BPS) black holes in $\mathcal{N}=8$ supergravity, as a potentially solvable model of gravitational dynamics. As a diagnosis of hidden symmetries, we ask whether the perihelion of the orbits…

High Energy Physics - Theory · Physics 2019-09-04 Simon Caron-Huot , Zahra Zahraee

Recent intensive observations of the BL Lac object OJ 287 raise a lot of questions on the models of binary black holes, processing jets, rotating helical jets and thermal instability of slim accretion disks. After carefully analyzing their…

Astrophysics · Physics 2009-11-07 F. K. Liu , Xue-Bing Wu

If the activity of active galactic nuclei (AGNs) is predominantly induced by major galaxy mergers, then a significant fraction of AGNs should harbor binary massive black holes in their centers. We study the mass function of binary massive…

Cosmology and Nongalactic Astrophysics · Physics 2015-05-18 Kimitake Hayasaki , Yoshihiro Ueda , Naoki Isobe

The central engine of blazar OJ~287 is arguably the most notable supermassive black hole (SMBH) binary candidate that emits nano-Hertz (nHz) gravitational waves. This inference is mainly due to our ability to predict and successfully…

High Energy Astrophysical Phenomena · Physics 2025-04-09 Debabrata Deb , Achamveedu Gopakumar , Mauri J. Valtonen

The multipole moments of black holes in general relativity obey certain consistency relations known as the no-hair theorems. The details of this multipolar structure are imprinted into the gravitational waves emitted by binary black holes,…

General Relativity and Quantum Cosmology · Physics 2024-09-11 Nicholas Loutrel , Richard Brito , Andrea Maselli , Paolo Pani

Blazar OJ287 exhibits large thermal flares at least twice every 12 years. The times of these flares have been predicted successfully using the model of a quasi-Keplerian eccentric black hole binary where the secondary impacts the accretion…

Beyond all reasonable doubt, black holes are commonly found in the nuclei of most normal galaxies. In recent years, dynamical measurements of hole masses have transformed the study of their functioning and evolution. In particular, relating…

Astrophysics · Physics 2007-05-23 R. D. Blandford

A significant number of stellar-mass black-hole (BH) binaries may merge in galactic nuclei or in the surrounding gas disks. With purposed space-borne gravitational-wave observatories, we may use such a binary as a signal carrier to probe…

General Relativity and Quantum Cosmology · Physics 2021-01-20 Hang Yu , Yanbei Chen

One of the most intriguing scenarios proposed to explain how active galactic nuclei are triggered involves the existence of a supermassive binary black hole system in their cores. Here we present an observational evidence for the first…

High Energy Astrophysical Phenomena · Physics 2012-10-30 E. Bon , P. Jovanović , P. Marziani , A. I. Shapovalova , N. Bon , V. Borka Jovanović , D. Borka , J. Sulentic , L. Č. Popović
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