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arXiv · 1003.6029

A likely candidate of type Ia supernova progenitors: the X-ray pulsating companion of the hot subdwarf HD 49798

Bo Wang·Zhanwen Han
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Abstract

HD 49798 is a hydrogen depleted subdwarf O6 star and has an X-ray pulsating companion (RX J0648.0-4418). The X-ray pulsating companion is a massive white dwarf. Employing Eggleton's stellar evolution code with the optically thick wind assumption, we find that the hot subdwarf HD 49798 and its X-ray pulsating companion could produce a type Ia supernova (SN Ia) in future evolution. This implies that the binary system is a likely candidate of SN Ia progenitors. We also discussed the possibilities of some other WD + He star systems (e.g. V445 Pup and KPD 1930+2752) for producing SNe Ia.

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Bo Wang, Zhanwen Han. 2010-03-31. A likely candidate of type Ia supernova progenitors: the X-ray pulsating companion of the hot subdwarf HD 49798. https://doi.org/10.1088/1674-4527/10/7/007

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