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arXiv · 1004.3065

The mass of the white dwarf in GW Libra

L. van Spaandonk·D. Steeghs·T. R. Marsh·S. G. Parsons
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Abstract

We report a mass and rotational broadening (vsini) for the pulsating white dwarf component of the WZ Sge type Dwarf Nova GW Lib based on high-resolution VLT spectroscopy that resolves the MgII 4481A absorption feature. Its gravitational redshift combined with white dwarf mass-radius models, provides us with a direct measurement of the white dwarf mass of M_1 = 0.84 pm 0.02 M_sun. The line is clearly resolved and if associated with rotational broadening gives vsini=87.0 pm 3.4 km/s, equivalent to a spin period of 97 pm 12s.

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L. van Spaandonk, D. Steeghs, T. R. Marsh, S. G. Parsons. 2010-04-18. The mass of the white dwarf in GW Libra. https://doi.org/10.1088/2041-8205%2F715%2F2%2Fl109

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