THERMAL AND ELECTRICAL CONDUCTIVITIES OF COULOMB CRYSTALS IN NEUTRON-STARS AND WHITE-DWARFS

Thermal and electrical conductivities are calculated for degenerate el ectrons scattered by phonons in a crystal consisting of atomic nuclei. The exact phonon spectrum and the Debye-Waller factor are taken into consideration. Monte Carlo calculations are performed for body-centere d cubic (bcc) crystals made up of C, O, Ne, Mg, Si, S, Ca, and Fe nucl ei ranging in density from 10(3) to 10(11) g cm(-3) at temperatures lo wer than the melting point but higher than the temperature at which Um klapp processes begin to ''freeze out''. A simplified method of calcul ation is proposed which makes it possible to describe the results in t erms of simple analytic expressions, to extend these expressions to an y species of nucleus, and to consider face-centered cubic (fcc) crysta ls. The kinetic coefficients are shown to depend tangibly on the type of crystal. The results are applicable to studies of heat transfer and the evolution of a magnetic field in the cores of white dwarfs and in the crusts of neutron stars. The thermal drift of a magnetic field in the crust of a neutron star is discussed.