More Optical Spectroscopy of the X-ray Nova J0422+32

Garcia, M. R.; Callanan, P.; McClintock, J.; Zhao, P.
Bibliographical reference

American Astronomical Society, 185th AAS Meeting, #11.04; Bulletin of the American Astronomical Society, Vol. 26, p.1324

Advertised on:
12
1994
Number of authors
4
IAC number of authors
0
Citations
1
Refereed citations
1
Description
We present the most recent results from our optical spectroscopy campaign on the X-ray Nova/Black Hole Candidate GRO J0422+32. Spectroscopy from the MMT during September 1994, when the system was at R=21 shows that the equivalent width of the H-alpha emission line is 150 Angstroms. Earlier Spectroscopy from March 1994, when the system was at R=20, shows a equivalent width of 100 Angstroms, and from Oct 1993, when the system was at R=19, shows an equivalent width of ~ 40 Angstroms. From our extensive Oct 1993 data, we find H-alpha velocity variations on a 5.1 hour period with a semi-amplitude of K=30km/sec. The relative phasing of these velocity variations and the photometric and velocity variation of the He-II 4686 emission line found by Casares et.al 1994 (poster paper at IAUS 165) may be taken as evidence that the mass of the compact object is M_x > 9.3{Msun}, the mass ratio q ~ 0.04, and the photometric variations may be caused by a either a x-ray heating effect or a partial eclipse of the disk by the secondary. However, these conclusions are not secure, and must be confirmed by observations of the system in quiescence.