Three-dimensional delayed-detonation models with nucleosynthesis for Type Ia supernovae. (arXiv:1211.3015v1 [astro-ph.SR]):
We present results for a suite of fourteen three-dimensional, high resolution
hydrodynamical simulations of delayed-detonation modelsof Type Ia supernova (SN
Ia) explosions. This model suite comprises the first set of three-dimensional
SN Ia simulations with detailed isotopic yield information. As such, it may
serve as a database for Chandrasekhar-mass delayed-detonation model
nucleosynthetic yields and for deriving synthetic observables such as spectra
and light curves. We employ a physically motivated, stochastic model based on
turbulent velocity fluctuations and fuel density to calculate in situ the
deflagration to detonation transition (DDT) probabilities. To obtain different
strengths of the deflagration phase and thereby different degrees of
pre-expansion, we have chosen a sequence of initial models with 1, 3, 5, 10,
20, 40, 100, 150, 200, 300, and 1600 (two different realizations) ignition
kernels in a hydrostatic white dwarf with central density of 2.9 x 10^9 gcc,
plus in addition one high central density (5.5 x 10^9 gcc), and one low central
density (1.0 x 10^9 gcc) rendition of the 100 ignition kernel configuration.
For each simulation we determined detailed nucleosynthetic yields by
post-processing 10^6 tracer particles with a 384 nuclide reaction network. All
delayed detonation models result in explosions unbinding the white dwarf,
producing a range of 56Ni masses from 0.32 to 1.11 solar masses. As a general
trend, the models predict that the stable neutron-rich iron group isotopes are
not found at the lowest velocities, but rather at intermediate velocities
(~3,000 - 10,000 km/s) in a shell surrounding a 56Ni-rich core. The models
further predict relatively low velocity oxygen and carbon, with typical minimum
velocities around 4,000 and 10,000 km/s, respectively.
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