2010/02/23 by M. Fink, F. K. Roepke, F. K. Röpke +5 · 441 citations
Chemistry · Physics and Astronomy · #Astrophysics #Atomic physics #Chandrasekhar limit #Chemistry #Detonation #Explosive material #Gamma-ray bursts and supernovae #Helium #Materials science #Mechanics #Nuclear physics #Physics #Pulsars and Gravitational Waves Research #Shell (structure) #Stellar, planetary, and galactic studies #Supernova #White dwarf #astro-ph.SR
paper · pdf · doi:10.1051/0004-6361/200913892
published in Astronomy and Astrophysics 514, A53 (EDP Sciences) · 10 pages, 10 figures; v2: typos corrected, accepted by Astronomy & Astrophysics
openalex publication_date 2010/02/23 · arxiv created 2010/10/22 · arxiv updated 2010/10/25 · openalex created_date 2020/11/23 · openalex updated_date 2026/08/05
The explosion of sub-Chandrasekhar mass white dwarfs via the double detonation scenario is a potential explanation for type Ia supernovae. In this scenario, a surface detonation in a helium layer initiates a detonation in the underlying carbon/oxygen core leading to an explosion. For a given core mass, a lower bound has been determined on the mass of the helium shell required for dynamical burning during a helium flash, which is a necessary prerequisite for detonation. For a range of core and corresponding minimum helium shell masses, we investigate whether an assumed surface helium detonation is capable of triggering a subsequent detonation in the core even for this limiting case. We carried out hydrodynamic simulations on a co-expanding Eulerian grid in two dimensions assuming rotational symmetry. The detonations are propagated using the level-set approach and a simplified scheme for nuclear reactions that has been calibrated with a large nuclear network. The same network is used to determine detailed nucleosynthetic abundances in a post-processing step. Based on approximate detonation initiation criteria in the literature, we find that secondary core detonations are triggered for all of the simulated models, ranging in core mass from 0.810 up to 1.385 with corresponding shell masses from 0.126 down to 0.0035 . This implies that, as soon as a detonation triggers in a helium shell covering a carbon/oxygen white dwarf, a subsequent core detonation is virtually inevitable.