Change search
ReferencesLink to record
Permanent link

Direct link
The viscous evolution of white dwarf merger remnants
Show others and affiliations
2012 (English)In: Monthly notices of the Royal Astronomical Society, ISSN 0035-8711, E-ISSN 1365-2966, Vol. 427, no 1, 190-203 p.Article in journal (Refereed) Published
Abstract [en]

The merger of two white dwarfs (WDs) creates a differentially rotating remnant which is unstable to magnetohydrodynamic instabilities. These instabilities can lead to viscous evolution on a time-scale short compared to the thermal evolution of the remnant. We present multidimensional hydrodynamic simulations of the evolution of WD merger remnants under the action of an alpha-viscosity. We initialize our calculations using the output of eight WD merger simulations from Dan et al., which span a range of mass ratios and total masses. We generically find that the merger remnants evolve towards spherical states on time-scales of hours, even though a significant fraction of the mass is initially rotationally supported. The viscous evolution unbinds only a very small amount of mass (less than or similar to 10(-5)M(circle dot)). Viscous heating causes some of the systems we study with He WD secondaries to reach conditions of nearly-dynamical burning. It is thus possible that the post-merger viscous phase triggers detonation of the He envelope in some WD mergers, potentially producing a Type Ia supernova via a double-detonation scenario. Our calculations provide the proper initial conditions for studying the long-term thermal evolution of WD merger remnants. This is important for understanding WD mergers as progenitors of Type Ia supernovae, neutron stars, R Coronae Borealis stars and other phenomena.

Place, publisher, year, edition, pages
2012. Vol. 427, no 1, 190-203 p.
Keyword [en]
hydrodynamics, supernovae: general, white dwarfs
National Category
Astronomy, Astrophysics and Cosmology
URN: urn:nbn:se:su:diva-84772DOI: 10.1111/j.1365-2966.2012.21993.xISI: 000310675400016OAI: diva2:582063


Available from: 2013-01-03 Created: 2013-01-02 Last updated: 2013-01-03Bibliographically approved

Open Access in DiVA

No full text

Other links

Publisher's full text

Search in DiVA

By author/editor
Rosswog, Stephan
By organisation
Department of AstronomyThe Oskar Klein Centre for Cosmo Particle Physics (OKC)
In the same journal
Monthly notices of the Royal Astronomical Society
Astronomy, Astrophysics and Cosmology

Search outside of DiVA

GoogleGoogle Scholar
The number of downloads is the sum of all downloads of full texts. It may include eg previous versions that are now no longer available

Altmetric score

Total: 11 hits
ReferencesLink to record
Permanent link

Direct link