Ignition of detonation in accreted helium envelopes

S. Ami Glasner*, E. Livne, E. Steinberg, A. Yalinewich, James W. Truran

*Corresponding author for this work

Research output: Contribution to journalArticlepeer-review

20 Scopus citations

Abstract

Sub-Chandrasekhar CO white dwarfs accreting helium have been considered as candidates for Type Ia supernova (SNIa) progenitors since the early 1980s (helium shell mass > 0.1M). These models, once detonated, did not fit the observed spectra and light curve of typical SNIa observations. New theoretical work examined detonations on much less massive (< 0.05M) envelopes. They find stable detonations that lead to light curves, spectra, and abundances that compare relatively well with the observational data. The exact mechanism leading to the ignition of helium detonation is a key issue, since it is a mandatory first step for the whole scenario. As the flow of the accreted envelope is unstable to convection long before any hydrodynamic phenomena develops, a multidimensional approach is needed in order to study the ignition process. The complex convective reactive flow is challenging to any hydrodynamical solver. To the best of our knowledge, all previous 2D studies ignited the detonation artificially. We present here, for the first time, fully consistent results from two hydrodynamical 2D solvers that adopt two independent accurate schemes. For both solvers, an effort was made to overcome the problematics raised by the finite resolution and numerical diffusion by the advective terms. Our best models lead to the ignition of a detonation in a convective cell. Our results are robust and the agreement between the two different numerical approaches is very good.

Original languageAmerican English
Pages (from-to)2238-2248
Number of pages11
JournalMonthly Notices of the Royal Astronomical Society
Volume476
Issue number2
DOIs
StatePublished - 11 May 2018

Bibliographical note

Publisher Copyright:
© 2018 The Author(s).

Keywords

  • Hydrodynamics
  • Methods: numerical
  • White dwarfs

Fingerprint

Dive into the research topics of 'Ignition of detonation in accreted helium envelopes'. Together they form a unique fingerprint.

Cite this