摘要
We examine the effects of symmetry energy on proto-neutron stars(PNSs)using an equation of state(EOS)described by the relativistic mean-field(RMF)model.The thermal properties of dense matter and the bulk properties of PNSs are investigated under the assumptions of isothermy,isentropy,and fixed lepton fractions.The polytropic index is calculated at finite temperature,revealing a negative correlation with the maximum mass of a PNS that the EOS can support.The properties of PNSs during the heating and cooling stages along their evolutionary path are explored under different combinations of lepton fraction and entropy.We investigate the correlation between symmetry energy slope L and the properties of PNSs.As L increases,the radius of a PNS also increases;however,this effect diminishes with a growing lepton fraction in the isentropic case.These results indicate that nuclear symmetry energy and its density dependence play crucial roles in determining the properties of PNSs and their evolutionary stages.
基金
Supported by the National Natural Science Foundation of China(12305148,11975132,12205158)
the Natural Science Foundation of Hebei Province,China(A2023203055)
the Natural Science Foundation of Shandong Province,China(ZR2023QA112,ZR2022JQ04,ZR2021QA037,ZR2019YQ01)。
