Nonequilibrium thermodynamics of accreted neutron-star crust

Abstract

We show that, in order to determine the equation of state of the inner crust of an accreting neutron star, one should minimize not the Gibbs free energy, as it is generally assumed in the literature, but a different thermodynamic potential $\Psi$, which tends to the minimum at fixed pressure and neutron chemical potential. Once this potential is specified, one can calculate the heat-release distribution in the stellar crust due to nonequilibrium nuclear reactions induced by accretion of matter onto the neutron-star surface. The results are important for adequate modeling of the accreted crust and interpretation of the observations of accreting neutron stars in low-mass X-ray binaries.

6 pages, accepted for publication in Phys. Rev. D (Letters)

References in corpus (8)

• Models of crustal heating in accreting neutron stars
• Neutron drip transition in accreting and nonaccreting neutron star crusts
• Thermal evolution of relativistic hyperonic compact stars with calibrated equations of state
• Thermal states of neutron stars with a consistent model of interior
• Crust structure and thermal evolution of neutron stars in soft X-ray transients
• Thermodynamically consistent equation of state for an accreted neutron star crust
• Heat release in accreting neutron stars
• Deep crustal heating for realistic compositions of thermonuclear ashes

Cited by in corpus (5)

• Fast neutrino cooling in the accreting neutron star MXB 1659-29
• Accreting neutron stars: heating of the upper layers of the inner crust
• Accreting neutron stars: composition of the upper layers of the inner crust
• Gapless neutron superfluidity in the crust of the accreting neutron stars KS 1731-260 and MXB 1659-29
• Pressure and chemical potentials in the inner crust of a cold neutron star within Hartree-Fock and extended Thomas-Fermi methods