University of Basel, Dept. of Physics and Astronomy
Klingelbergstrasse 82
Sure
4056
Basel, Switzerland
Presentation 1 : Oral/Invited
The Physics of Supernova Explosions: Current Knowledge and Review of Existing Models
F.-K, Thielemann, F. Brachwitz, P. Höflich, G. Martinez-Pinedo, K. Nomoto
The basic recipe of SN Ia explosions is simple:
A white dwarf, growing towards the Chandrasekhar mass, contracts and ignites
under degenerate conditions, causing a thermonuclear runaway. Burning $^{12}$C
and $^{16}$O to $^{56}$Ni can produce a purely nuclear explosion energy of
about 1.5$\times 10^{51}$erg and disrupt the original white dwarf completely.
The subtraction of the gravitational binding energy of the white dwarf plus
the observed fact that not all material is burned to Fe/Ni (rather to
intermediate elements like Mg, Si, S, Ca) leads to the observed explosion
energy. The decay ($^{56}$Ni $\rightarrow$) $^{56}$Co $\rightarrow$ $^{56}$Fe
can explain the light curve. \\
The remaining questions are: How can cool and stable white dwarfs be turned
into exploding objects via binary mass exchange; what variety in original
white dwarf sizes, metallicities and accretion scenarios is expected; how does
the ignition occur and how does the burning front propagate; how does this
relate to burning conditions, energy generation, nucleosynthesis results,
$^{56}Ni masses and the small observed variety in explosive events; how can
observed spectra (and their Doppler broadening) act as diagnostics for
explosion models and nucleosynthesis predictions? \\
We will address (and review) these issues within existing 1D spherically
symmetric models with parametrized burning front prescription and attempt
to discuss the relation to multi-D models.