OJ 287: Binary Pair of Supermassive Black Holes
Abstract
A light curve of the BL Lacertae object OJ 287 is constructed in the optical V band using observations between the year 1890 and the present. The light curve shows repeated outbursts at ~11.65 yr intervals. Also there is a hint of repeated minima at the interval of 11.0 yr. The structure of the light curve during an outburst resembles the pattern of inflow of gas from an accretion disk to a supermassive black hole in a tidal perturbation. For this reason we propose that OJ 287 is a binary pair of supermassive black holes with an orbital period of 9 yr in the rest frame of OJ 287 and that the light variations are related to tidally induced mass flows from accretion disks into black holes. Numerical experiments using N-body code by Miller have been carried out to study mass flows. These simulations show that the inflow into the center of a black hole disk during repeated periastron passages of the companion will produce an outburst pattern similar to that observed for OJ 287 with 9 yr period. Indirect observational evidence indicates masses for two black holes of 5 x 10^9^ M_sun_ and 2 x 10^7^ M_sun_ with a binary semimajor axis of ~0.1 pc. The future binary lifetime via gravitational radiation is ~10^5^ yr. Tidal interaction and thus luminosity of the binary model would be greatest in these last stages which is consistent with OJ 287 being one of the brightest quasars.
- Publication:
-
The Astrophysical Journal
- Pub Date:
- February 1988
- DOI:
- 10.1086/166033
- Bibcode:
- 1988ApJ...325..628S
- Keywords:
-
- Binary Stars;
- Bl Lacertae Objects;
- Black Holes (Astronomy);
- Supermassive Stars;
- Extragalactic Radio Sources;
- Light Curve;
- Many Body Problem;
- Periodic Variations;
- Stellar Mass Accretion;
- Astrophysics;
- BLACK HOLES;
- BL LACERTAE OBJECTS