Optical spectroscopy of (candidate) ultra-compact X-ray binaries
نویسندگان
چکیده
We present (preliminary) results of our systematic spectroscopic study of (candidate) ultra-compact X-ray binaries. Most candidates are confirmed and we found the first optical spectra of (pure) carbon-oxygen accretion discs.
منابع مشابه
Ultra-compact (X-ray) binaries
A short review of ultra-compact binaries, focused on ultra-compact X-ray binaries, is followed by a discussion of recent results of our VLT campaign to obtain optical spectra of (candidate) ultra-compact X-ray binaries. We find evidence for carbon/oxygen as well as helium/nitrogen discs and no evidence for (traces) of hydrogen. This suggests that the donors in the observed systems are white dwa...
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