ROLE OF DISTRIBUTION FUNCTION ON CHARACTERISTIC PROPERTIES OF SUPERNOVA MATTER

Abstract

Supernova matter consisting of protons, neutrons and electrons with proton fraction yp = 0.3 are studied within finite temperature Brueckner–Goldstone approach with effective two-body Sussex interaction for various values of densities and at temperatures T = 5, 7 and 10 MeV. It is found that at a given density, temperature and proton fraction, the entropy production, internal energy per nucleon, free energy per nucleon and pressure generated by protons and electrons are not equal. Entropy produced in the supernova matter is larger than that of corresponding asymmetric nuclear matter. The rise in temperature with densities in this matter under adiabatic condition is relatively suppressed with respect to corresponding asymmetric nuclear matter. Contribution to internal energy and free energy due to electron components is more pronounced than those of nuclear components. But the contribution to entropy and pressure due to nuclear components is larger than those of electron components. It is observed that for the matter with proton fraction yp = 0.1, the internal energy, free energy and pressure generated due to protons are density-independent whereas, for supernova matter, these quantities are density-dependent. Distribution function, fraction of particles and mean field are the key factors to explain the characteristic properties of the constituent particles of supernova matter.