arXiv subjects

J. B. Wei

Publications and source records attributed to J. B. Wei.

2 recordsLinked to original sources

arXiv2025

Cooling of dark neutron stars

We study the cooling of isolated dark-matter-admixed neutron stars, employing a realistic nuclear equation of state and realistic nuclear pairing gaps, together with fermionic dark matter of variable particle mass and dark-matter fraction. The related parameter space is scanned for the stellar structural and cooling properties. We find that a consistent description of all current cooling data requires fast direct Urca cooling and reasonable proton 1S0 gaps. Dark matter affects the cooling properties by a modification of the nuclear density profiles, but also changes stellar radius and maximum mass. Possible signals of a large dark matter content could be a very massive but slow-cooling star or a very light but fast-cooling star.

astro-ph.HE↗

arXiv2024

Radial oscillations of proto-neutron stars

We investigate radial oscillations of proto-neutron stars, employing equations of state described by the Brueckner-Hartree-Fock theory or the relativistic mean field model, and assuming isentropy and fixed lepton fractions for the internal structure. We calculate the eigenfrequencies and corresponding oscillation functions, which show different characteristics in different mass regions. In the low-mass region around 1.4 solar mass, the radial oscillation frequencies are lowered by large entropy and neutrino trapping, along with a reduction of the average adiabatic index. In the region close to the maximum mass, the fundamental oscillation frequency drops rapidly and vanishes at the maximum mass, in accordance with the critical stability criterion $\partial M /\partial ρ_c = 0$, as for cold neutron stars.

nucl-th↗