Type Ia supernova diversity in three-dimensional models

Free access article

Issue		A&A Volume 453, Number 1, July I 2006


Page(s)		203 - 217
Section		Stellar structure and evolution
DOI		http://dx.doi.org/10.1051/0004-6361:20053430

A&A 453, 203-217 (2006)
DOI: 10.1051/0004-6361:20053430

Type Ia supernova diversity in three-dimensional models

F. K. Röpke¹, M. Gieseler¹, M. Reinecke¹, C. Travaglio² and W. Hillebrandt¹

¹ Max-Planck-Institut für Astrophysik, Karl-Schwarzschild-Str. 1, 85741 Garching, Germany
e-mail: [fritz;mccg;martin;wfh]@mpa-garching.mpg.de
² INAF - Osservatorio Astronomico di Torino, Strada dell'Osservatorio 20, 10025 Pino Torinese, Torino, Italy
e-mail: travaglio@to.astro.it

(Received 13 May 2005 / Accepted 6 January 2006)

Abstract
Context.The use of type Ia supernovae as distance indicators for cosmology has initiated a search for theoretical arguments supporting the empirical calibration methods applied. As a first step, a sound understanding of the origin of the observed diversity in type Ia supernova properties is needed.
Aims.Here we present a systematic study of effects resulting from changing some physical parameters of three-dimensional deflagration models of thermonuclear supernovae.
Methods.The high computational costs of such models restricted this survey to simple setups which are known to result in weak explosions and therefore we point out trends rather then setting the absolute scale of the variance. In our study we vary the progenitor's carbon-to-oxygen ratio and its central density prior to ignition because both properties are not well determined by stellar evolution theory and they may change from supernova to supernova. Next we compute for these explosion models the nucleosynthesis yields in a post-processing step. This, in addition, allows us to study variations in the progenitor's metallicity by means of different ²²Ne mass fractions in the initial composition.
Results.We find that the progenitor's carbon-to-oxygen ratio and its central density affect the energy release of the models and thus the expansion velocity of the supernova. Moreover, we find that changing the metallicity and the central density changes the production of radioactive ⁵⁶Ni and thus affects the luminosity. In contrast, the carbon-to-oxygen ratio has little effect on the ⁵⁶Ni production.
Conclusions.Implications of the variations of the explosion energy and the produced ⁵⁶Ni mass for type Ia supernova diversity are discussed.

Key words: stars: supernovae: general -- hydrodynamics -- nuclear reactions, nucleosynthesis, abundances -- methods: numerical

What is OpenURL?

The OpenURL standard is a protocol for transmission of metadata describing the resource that you wish to access. An OpenURL link contains article metadata and directs it to the OpenURL server of your choice. The OpenURL server can provide access to the resource and also offer complementary services (specific search engine, export of references...). The OpenURL link can be generated by different means.

If your librarian has set up your subscription with an OpenURL resolver, OpenURL links appear automatically on the abstract pages.
You can define your own OpenURL resolver with your EDPS Account. In this case your choice will be given priority over that of your library.
You can use an add-on for your browser (Firefox or I.E.) to display OpenURL links on a page (see http://www.openly.com/openurlref/). You should disable this module if you wish to use the OpenURL server that you or your library have defined.