Bibcode
Barnes, A. D.; Casares, J.; Charles, P. A.; Clark, J. S.; Cornelisse, R.; Knigge, C.; Steeghs, D.
Bibliographical reference
Monthly Notices of the Royal Astronomical Society, Volume 365, Issue 1, pp. 296-302.
Advertised on:
1
2006
Citations
26
Refereed citations
20
Description
We present high-resolution optical spectroscopy of the X-ray binary
system SS433, obtained over a wide range of orbital phases. The spectra
display numerous weak absorption features, and include the clearest
example seen to date of those features (resembling a mid-A type
supergiant spectrum), which have previously been associated with the
mass-donor star. However, the new data preclude the hypothesis that
these features originate solely within the photosphere of the putative
mass donor, indicating that there may be more than one region within the
system producing an A supergiant-like spectrum, probably an accretion
disc wind. Indeed, whilst we cannot confirm the possibility that the
companion star is visible at certain phase combinations, it is possible
that all supergiant-like features observed thus far are produced solely
in a wind. We conclude that great care must be taken when interpreting
the behaviour of these weak features.