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The Recurrent Nova U Scorpii - A Type Ia Supernova Progenitor

T. D. Thoroughgood·V. S. Dhillon·S. P. Littlefair·T. R. Marsh·D. A. Smith
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Abstract

We derive the mass of the white dwarf in the eclipsing recurrent nova U Sco from the radial velocity semi-amplitudes of the primary and secondary stars. Our results give a high white dwarf mass of M_1 = 1.55 \pm 0.24M_\odot, consistent with the thermonuclear runaway model of recurrent nova outbursts. We confirm that U Sco is the best Type Ia supernova progenitor known, and predict that the time to explosion is within ~700,000 years.

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T. D. Thoroughgood, V. S. Dhillon, S. P. Littlefair, T. R. Marsh, D. A. Smith. 2001-09-28. The Recurrent Nova U Scorpii - A Type Ia Supernova Progenitor. https://arxiv.org/abs/astro-ph/0109553

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