A TiO study of the black-hole binary GRO J0422+32 in a very low state

Details A TiO study of the black-hole binary GRO J0422+32 in a very low state A TiO study of the black-hole binary GRO J0422+32 in a very low state

2000-04-17

arxiv.org/abs/astro-ph/0004235v1

Mon.Not.Roy.Astron.Soc. 317 (2000) 528

Astronomy and Astrophysics

Astrophysics

(1) Department of Physics, Keele University, Keele, Staffordshire, ST5 5BG (2) Department of Astrophysics, Nuclear Physics Lab

Scientific paper

10.1046/j.1365-8711.2000.03608.x

We present 53 simultaneous photometric (I band) and spectroscopic (6900-9500 Angstroms) observations of J0422+32, taken during December 1997. From these we determine that J0422+32 was in its lowest state yet observed, at I=20.44+/-0.08. Using relative spectrophotometry, we show that it is possible to correct very accurately for telluric absorption. Following this, we use the TiO bands at 7055 Angstroms and 7589 Angstroms for a radial velocity study and thereby obtain a semi-amplitude of 378+/-16kms-1, which yields f(M)=1.191+/-0.021M_solar and q=9.0+2.2-2.7, consistent with previous observations. We further demonstrate that this little explored method is very powerful for such systems. We also determine a new orbital ephemeris of HJD=2450274.4156+/-0.0009 + 0.2121600+/-0.0000002E. We see some evidence for an ellipsoidal modulation, from which we determine the orbital inclination of J0422+32 to be less than 45 degrees. We therefore calculate a minimum mass for the primary of 2.22M_solar, consistent with a black hole, but not necessarily the super-massive one proposed by Beekman et al (1997). We obtain an M4-5 spectral type for the secondary star and determine that the secondary contributes 38+/-2% of the flux that we observe from J0422+32 over the range 6950-8400 Angstroms. From this we calculate the distance to the system to be 1.39+/-0.15kpc.

Affiliated with

Also associated with

No associations

Rating

A TiO study of the black-hole binary GRO J0422+32 in a very low state 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 A TiO study of the black-hole binary GRO J0422+32 in a very low state, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and A TiO study of the black-hole binary GRO J0422+32 in a very low state will most certainly appreciate the feedback.

Rate now

Comments { 0 }

Profile ID: LFWR-SCP-O-589469