Speaker
Prof.
Francesca GULMINELLI
(LPC and University of Caen)
Description
The construction of a realistic equation of state for dense matter as it can be found in core-collapse supernovae and neutron stars is a formidable task which is not yet completely achieved. The structure of very high density matter in the neutron star core is by far the most uncertain part of the EoS modeling. However, even in the least exotic regime of sub-saturation matter, where the degrees of freedom are purely nucleonic and relatively well-known, the presence of clustering due to the Coulomb quenching of the nuclear liquid-gas phase transition requires beyond mean-field methods properly treating all the complexity of nuclear structure, in a regime of neutron-rich matter where no experimental data exist to validate the available effective interactions.
Self-consistent mean-field approaches with realistic effective interactions are still routinously applied at zero temperature. This is justified thanks to the Wigner-Seitz structure of stellar matter, which reduces the thermodynamic limit to a single nucleus problem. However, a consistent treatment at finite temperature in principle implies beyond mean-field configuration mixing. This is presently a problem since existing models are either done in the single nucleus approximation, or do not recover the single-nucleus Wigner-Seitz limit of zero temperature.
In this talk we will present a density-functional formalism which, by introducing explicit cluster degrees of freedom, consistently describes the neutron-rich nuclei immersed in the gas of their continuum states in the inner crust, and the nuclear statistical equilibrium of different in-medium modified nuclear species in supernova matter. The influence of the effective interaction, and specifically the density dependence of the symmetry energy, will also be discussed.
Primary author
Prof.
Francesca GULMINELLI
(LPC and University of Caen)
