Is KPD 1930+2752 a good candidate type Ia supernova progenitor?

¹ Physics Department, Tartu University, Ülikooli 18, 50090 Tartu, Estonia
² Observatory, PO Box 14, 00014, University of Helsinki, Finland
³ Institute of Astronomy, 48 Pyatnitskaya Str., 109017 Moscow, Russia e-mail: afed, lry@inasan.rssi.ru
⁴ Astronomical Institute "Anton Pannekoek" , Kruislaan 403, 1098 SJ Amsterdam, The Netherlands

Corresponding author: E. Ergma, ene@physic.ut.ee

Received: 14 May 2001
Accepted: 16 July 2001

Abstract

We investigate the evolution of a binary system which initially has an orbital period of 2h17m and contains a 0.5 helium star with a white dwarf companion of 0.97 , similar to the suggested SN Ia candidate progenitor KPD 1930+2752. We show that the helium star completes core helium burning and becomes a white dwarf before the components merge. The most probable outcome of the merger of the components is the formation of a massive white dwarf, despite the fact that initially the total mass of the system is above the Chandrasekhar mass.