The DelayedDetonation Model of Type IA Supernovae I. The Deflagration Phase
Abstract
The nature of the 'delayed detonation' mechanism of Khokhlov for the explosion of Type Ia supernovae is investigated by using twodimensional numerical hydrodynamics simulations. A new algorithm is used to treat the deflagration front. Assuming that it propagates locally at the laminar flame speed, the deflagration is insufficient to unbind the star. Expansion shuts of the flame; much of this small production of iron group nuclei occurs at lower densities, which reduces the electroncapture problem. The burning front does become wrinkled, but the wavelength of the instability is much larger than the computational grid size and is resolved; this is consistent with previous analysis. Because the degenerate star has an adiabatic exponent only slightly above 4/3, the energy released by deflagration drives a pulsation of large amplitude. During the first expansion phase, adiabatic cooling shuts off the burning, and a RayleighTaylor instability then gives mixing of highentropy ashes with lowentropy fuel. During the first contraction phase, compressional heating reignites the material. This paper deals with the deflagration phase, from the onset of burning, through expansion and quenching of the flame, to the first contraction.
 Publication:

The Astrophysical Journal
 Pub Date:
 May 1994
 DOI:
 10.1086/174142
 Bibcode:
 1994ApJ...427..315A
 Keywords:

 Hydrodynamics;
 Mathematical Models;
 Nuclear Fusion;
 Nuclear Interactions;
 Stars;
 Stellar Mass;
 Supernovae;
 Algorithms;
 Applications Of Mathematics;
 Flux Density;
 Radiation Pressure;
 Statistical Distributions;
 Wavelengths;
 Astrophysics;
 HYDRODYNAMICS;
 NUCLEAR REACTIONS;
 NUCLEOSYNTHESIS;
 ABUNDANCES;
 STARS: SUPERNOVAE: GENERAL