Speaker
Kristian Petrik
(Institute of Physics, Slovak Academy of Sciences)
Description
Recent progress in astronomical observations, namely accurate estimation of the mass of the pulsars J1614-2230 and J0348+0432, which yields values around 2 M_sol, demands that any reliable nuclear equation of state (EoS) should be able to reproduce these results. Common feature of models that include hyperon degrees of freedom, kaon condensates or other forms of exotic hadronic matter, is softening of the EoS along with the appearance of such particles. The density dependent relativistic hadron field (DDRHF) theory is no exception. To help improve, or overcome this issue, we present several new approaches to the effective density dependence of DDRHF models, which include an introduction of 2-parametric class of density dependent functions, as well as mapping of Fock exchange terms onto the mean-field theory. To estimate reliable parametrizations, we made fits of our models to the more fundamental Dirac-Brueckner-Hartree-Fock (DBHF) calculations, with the use of above techniques. Our results show promising improvements with respect to the compact star physics.
Author
Kristian Petrik
(Institute of Physics, Slovak Academy of Sciences)
Co-author
Dr
Stefan Gmuca
(Institute of Physics, Slovak Academy of Sciences)