Accreting white dwarf models for type 1 supernovae. 1. Presupernova evolution and triggering mechanisms

Technical Report · Sat Aug 01 00:00:00 EDT 1981

OSTI ID:5758900

Nomoto, K

As a plausible explosion model for a Type I supernova, the evolution of carbon-oxygen white dwarfs accreting helium in binary systems was investigated from the onset of accretion up to the point at which a thermonuclear explosion occurs. The relationship between the conditions in the binary system and the triggering mechanism for the supernova explosion is discussed, especially for the cases with relatively slow accretion rate. It is found that the growth of a helium zone on the carbon-oxygen core leads to a supernova explosion which is triggered either by the off-center helium detonation for slow and intermediate accretion rates or by the carbon deflagration for slow and rapid accretion rates. Both helium detonation and carbon deflagration are possible for the case of slow accretion, since in this case the initial mass of the white dwarf is an important parameter for determining the mode of ignition. Finally, various modes of building up the helium zone on the white dwarf, namely, direct transfer of helium from the companion star and the various types and strength of the hydrogen shell flashes are discussed in some detail.

• Research Organization: National Aeronautics and Space Administration, Greenbelt, MD (USA). Goddard Space Flight Center
• OSTI ID: 5758900
• Report Number(s): NASA-TM-83810
• Country of Publication: United States
• Language: English

Related Subjects

71 CLASSICAL AND QUANTUM MECHANICS
GENERAL PHYSICS
SUPERNOVAE
STAR MODELS
WHITE DWARF STARS
CARBON
HELIUM
HYDROGEN
OXYGEN
STAR ACCRETION
STAR EVOLUTION
THERMONUCLEAR EXPLOSIONS
DWARF STARS
ELEMENTS
ERUPTIVE VARIABLE STARS
EXPLOSIONS
FLUIDS
GASES
MATHEMATICAL MODELS
NONMETALS
NUCLEAR EXPLOSIONS
RARE GASES
STARS
VARIABLE STARS
640102* - Astrophysics & Cosmology- Stars & Quasi-Stellar
Radio & X-Ray Sources