Numerical Stability of Detonations in White Dwarf Simulations

Abstract

Some simulations of Type Ia supernovae feature self-consistent thermonuclear detonations. However, these detonations are not meaningful if the simulations are not resolved, so it is important to establish the requirements for achieving a numerically converged detonation. In this study we examine a test detonation problem inspired by collisions of white dwarfs. This test problem demonstrates that achieving a converged thermonuclear ignition requires spatial resolution much finer than 1 km in the burning region. Current computational resource constraints place this stringent resolution requirement out of reach for multi-dimensional supernova simulations. Consequently, contemporary simulations that self-consistently demonstrate detonations are possibly not converged and should be treated with caution.

Accepted for publication in the Astrophysical Journal