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Optical identification of supersoft X-ray sources in M31

Marina orio·Roberto Casalegno·Chris Conselice·Jochen Greiner·Petko L. Nedialkov·Nikolay A. Tikhonov
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Abstract

We report on initial progress in a program of optical identification of supersoft X-ray sources in M31, pursued mainly with the WIYN telescope. We propose the identification of one supersoft X-ray source with a variable star, which we believe to have been a classical or recurrent nova in outburst in September 1990. The nova remnant must have been still a supersoft X-ray sources 5 years after this observation, when it was observed with ROSAT.

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Marina orio, Roberto Casalegno, Chris Conselice, Jochen Greiner, Petko L. Nedialkov, Nikolay A. Tikhonov. 2001-02-26. Optical identification of supersoft X-ray sources in M31. https://arxiv.org/abs/astro-ph/0102441

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