The Supernova Equation of State: Potential vs. Field-Theoretical Approaches
C. Constantinou
Stony Brook
An important ingredient in simulations of core collapse supernova
(SN) explosions is the equation of state (EOS) of nucleonic matter for
densities extending from 10^-7 fm^-3 to 1 fm^-3, temperatures up to 50
MeV, and proton-to-baryon fraction in the range 0 to 1/2. In this work we
study supernova matter using a non-relativistic potential model as well
as a relativistic mean-field theoretical one. In the former approach, we
employ the Skyrme-like Hamiltonian density of Akmal, Pandharipande, and
Ravenhall which takes into account the long scattering lengths of nucleons
that determine the low density characteristics. In the latter, we use a
Walecka-like Lagrangian density supplemented by non-linear interactions
involving \sigma, \omega, and \rho meson exchanges, calibrated so that
known properties of nuclear matter are reproduced. We focus, initially,
on the bulk homogeneous phase and calculate its thermodynamic properties as
functions of baryon density, temperature, and proton-to-baryon ratio. The
exact results are then compared to approximate ones in the degenerate and
non-degenerate limits for which analytical formulae have been derived. Our
next steps would be to extend our calculations of the state variables to
the subnuclear region in which nuclei are present and perform comparisons
with the results of the supernova EOS by Lattimer and Swesty.
Date: | Mardi, le 3 avril 2012 |
Heure: | 14:30 |
Lieu: | Université McGill |
| Ernest Rutherford Physics Building, R.E. Bell Conference Room (room 103) |
Contact: | Robert Rutledge |
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