Measuring Black Hole Spin in OJ287

Astronomy and Astrophysics – Astronomy

Scientific paper

Rate now

  [ 0.00 ] – not rated yet Voters 0   Comments 0

Details

Scientific paper

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 outbursts in the light curve of OJ287. This identification allows an exact solution of the orbit, with very tight error limits. Nine outbursts from both the historical photographic records as well as from recent photometric measurements have been used as fixed points of the solution: 1913, 1947, 1957, 1973, 1983, 1984, 1995, 2005 and 2007 outbursts. This allows the determination of eight parameters of the orbit. Most interesting of these are the primary mass of 1.80 1010 solar mass, the secondary mass 1.2 108 solar mass, major axis precession rate 38.9 degrees per period, and the initial (at 1850) eccentricity of the orbit at apocenter 0.660. All decimals in these figures are significant, i.e. the probable error enters the next digit. The dimensionless spin parameter is not so well determined: its value is 0.465 +/- 0.01. The last parameter will be more tightly constrained in 2015 when the next outburst is due. The outburst should begin on September 25 if the spin value is at the upper end of this range, and on October 13 if the spin is at the lower end of its probable range. We have also tested the possibility that the quadrupole term in the Post Newtonian equations of motion does not exactly follow Einstein's theory: a parameter q is introduced as one of the 8 parameters. Its value is in the range q = 1.1 +/- 0.3, i.e. the Einstein's value q = 1 is well within the accepted range. This supports the `no-hair’ theorem of black holes within the achievable precision.

No associations

LandOfFree

Say what you really think

Search LandOfFree.com for scientists and scientific papers. Rate them and share your experience with other people.

Rating

Measuring Black Hole Spin in OJ287 does not yet have a rating. At this time, there are no reviews or comments for this scientific paper.

If you have personal experience with Measuring Black Hole Spin in OJ287, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Measuring Black Hole Spin in OJ287 will most certainly appreciate the feedback.

Rate now

     

Profile ID: LFWR-SCP-O-808748

  Search
All data on this website is collected from public sources. Our data reflects the most accurate information available at the time of publication.