Bibcode
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
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.