Density dependence of nuclear symmetry energy

Abstract

High density behaviour of nuclear symmetry energy is studied on the basis of a stiffest density dependence of asymmetric contribution to energy per nucleon in charge neutral n + p + e + µ matter under beta equilibrium. The density dependence of nuclear symmetry energy obtained in this way is neither very stiff nor soft at high densities and is found to be in conformity with recent observations of neutron stars PACS: 21.65.+f; 26.60.+c

Nuclear symmetry energy parameters from neutron skin thickness in 208Pb and electric dipole polarizability in 68Ni , 120Sn and 208Pb

“…Constraints from terrestrial nuclear laboratories and astrophysical observations have resolved the matter to some extent. High density behaviour of NSE has been studied in a recent work which shows that NSE which is neither very soft nor stiff at high density may be compatible to observations from neutron stars [73]. The upper limit of tidal deformability for canonical neutron stars Λ 1.4 = 580 extracted from GW170817 by LIGO and VIRGO collaborators [74] has allowed to constrain the high density nuclear equation of state to a narrow range.…”

Nuclear symmetry energy and neutron skin thickness of 208Pb using a finite range effective interaction

“…For an isospin asymmetric nuclear matter (ANM) with neutron-proton asymmetry δ, neutron density ρ n , proton density ρ p , the energy per nucleon e(ρ, δ) can be written as [42]…”

“…V(ρ, δ) is the interaction part of the equation of state, e(ρ, δ). The kinetic part of the EoS is treated in the relativistic Fermi gas model and the functional f (k i ) with i=n, p is expressed as [42] ( ) ( ) ( )…”

“…Here we have substituted the expression for Q from the relationship of t in equation(30) and defined a constant nucleus. In equation(42), the leading term is proportional to ( ) This expression in equation(42) allows us to draw a linear correlation…”