VLT optical observations of V821 Ara(=GX339-4) in an extended "off" state
Astrophysics
2016-08-30 v1
Abstract
We report on low-resolution spectroscopy of GX339-4 during its current, extended X-ray `off' state in May 2000 (r=20.1) obtained with the VLT Focal Reducer/low dispersion Spectrograph (FORS1). Although we do not positively detect the secondary star in GX339-4 we place an upper limit of 30 percent on the contribution of a ``normal'' K-type secondary star spectrum to the observed flux. Using this limit for the observed magnitude of the secondary star, we find a lower limit for the distance of GX339-4 to be 5.6 kpc.
Cite
@article{arxiv.astro-ph/0107455,
title = {VLT optical observations of V821 Ara(=GX339-4) in an extended "off" state},
author = {T. Shahbaz and R. Fender and P. A. Charles},
journal= {arXiv preprint arXiv:astro-ph/0107455},
year = {2016}
}
Comments
5 pages, 5 figures, AA letters