Mathematics – Logic
Scientific paper
Jun 2006
adsabs.harvard.edu/cgi-bin/nph-data_query?bibcode=2006aas...208.0206s&link_type=abstract
American Astronomical Society Meeting 208, #2.06; Bulletin of the American Astronomical Society, Vol. 38, p.79
Mathematics
Logic
Scientific paper
The lightcurves of Type Ia supernovae are known to be powered by the decay of radioactive nickel and cobalt isotopes, yet the mechanism for creating and ejecting these elements remains poorly understood. The need for better understanding becomes more pressing with constant improvement of observational data on local and cosmological supernovae. In the dense core of the igniting white dwarf, matter is burned by a passing flame (the deflagration) to a hot soup of ashes in nuclear statistical equilibrium (NSE), where continuously occurring particle fusion is balanced by photo-disintegration. This NSE state then evolves as the ashes undergo hydrodynamic evolution. As much as 40% of the available nuclear energy is released during this post-flame evolution, and proper calculation of this energy release is essential to simulations of the early stages of a supernova. We describe a treatment of the NSE material that, in addition to modeling energy released behind the flame, accurately accounts for electron capture, neutrino losses, and screening of charged particle reactions. These demonstrate the functionality of the model and illustrate the disparity between timescales for burning and neutronization at different densities. The screening utilized is, for the first time, fully consistent between the NSE calculation and the dynamic burning (nuclear network) calculation which models the flame itself. This treatment has been implemented in the FLASH code, and is being used to simulate the early stages of Type Ia supernovae. We present results of of 1-D simulations that demonstrate the functionality of the method. Precise calculation of the energy release is necessary for calculation of nucleosynthetic information for the ejecta. Comparison of such calculations with observed spectral characteristics of the ejecta has consistently proven one of the most powerful observational tools for understanding the supernova process.Supported by DOE contract No. B523820, NSF grant PHY 02-16783 and AST-0507456.
Calder Alan C.
Lamb Don Q.
Peng Fang
Seitenzahl Ivo R.
Townsley Dean M.
No associations
LandOfFree
Strong and Weak Nuclear Evolution of Material Behind a Deflagration Front in Type Ia Supernovae does not yet have a rating. At this time, there are no reviews or comments for this scientific paper.
If you have personal experience with Strong and Weak Nuclear Evolution of Material Behind a Deflagration Front in Type Ia Supernovae, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Strong and Weak Nuclear Evolution of Material Behind a Deflagration Front in Type Ia Supernovae will most certainly appreciate the feedback.
Profile ID: LFWR-SCP-O-1855062