David A. Chamulak et al 2007 ApJ 655 L93 doi:10.1086/511856
David A. Chamulak1, Edward F. Brown1,3 and Francis X. Timmes2
Show affiliationsCarbon-oxygen white dwarfs contain 22Ne formed from α-captures onto 14N during core He burning in the progenitor star. In a white dwarf (Type Ia) supernova, the 22Ne abundance determines, in part, the neutron-to-proton ratio and hence the abundance of radioactive 56Ni that powers the light curve. The 22Ne abundance also changes the burning rate and hence the laminar flame speed. We tabulate the flame speedup for different initial 12C and 22Ne abundances and for a range of densities. This increase in the laminar flame speed—about 30% for a 22Ne mass fraction of 6%—affects the deflagration just after ignition near the center of the white dwarf, where the laminar speed of the flame dominates over the buoyant rise, and in regions of lower density, ~107 g cm-3, where a transition to distributed burning is conjectured to occur. The increase in flame speed will decrease the density of any transition to distributed burning.
galaxies: evolution; nuclear reactions, nucleosynthesis, abundances; supernovae: general; white dwarfs
Issue 2 (2007 February 1)
Received 2006 October 31, accepted for publication 2006 December 15
Published 2007 January 16
David A. Chamulak et al 2007 ApJ 655 L93
Säm Krucker and Arnold O. Benz 1998 ApJ 501 L213
T. K. Sridharan et al. 2002 ApJ 566 931
G. B. Brammer et al 2009 ApJ 706 L173
Alex D Charpentier et al 2009 Environ. Res. Lett. 4 014005
M J Davis et al 1999 J. Phys. B: At. Mol. Opt. Phys. 32 3993
Eduardo González-Alfonso et al. 2004 ApJ 613 247
Debra A. Fischer and Jeff Valenti 2005 ApJ 622 1102
F Piquemal and G Genevès 2000 Metrologia 37 207
Gerrit L. Verschuur and Anthony L. Peratt 1999 The Astronomical Journal 118 1252