Equation of state in a strong magnetic field - Finite temperature and gradient corrections

Abstract

The equation of state for condensed matter in a strong magnetic field is constructed. The regime for which statistical models and spherical Wigner-Seitz lattice cells are valid approximations is treated. The equation of state for a free nonrelativistic homogeneous electron gas in a uniform magnetic field is examined as a function of temperature, after which this treatment is refined by incorporating Coulomb interactions in a magnetic Thomas-Fermi model which allows for finite temperature. Gradient corrections to the zero-temperature equation of state are then evaluated by constructing a magnetic Thomas-Fermi-Dirac-Weizsaecker model, these corrections having a considerable effect on the zero-pressure density for matter in strong magnetic fields. Finally, the hydrostatic equilibrium equation for the surface structure of a neutron star is integrated using the presently computed equations of state.