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The thermal resistivity of metals due to electron-electron scattering is calculated by using the static-screening potential with the screening length determined by the compressibility which is derived from the Monte-Carlo values for the correlation energy. The result is compared with other theories and experiment. It is found that the resistivity depends quite sensitively on the screening length, with the theory based on the approximate correlation energy differing significantly from the present result. Compared with other more sophisticated theories, the present simple model is found to agree with experiment reasonably and competitively well, and much better than the result with the Fermi-Thomas screened-Coulomb potential. The inclusion of core polarization and band mass changes the thermal resistivity by up to 35% for sodium, potassium, rubidium, and cesium and by an order of magnitude for lithium.

The effects of a finite neutrino magnetic dipole moment on the cooling of neutron stars are studied. It is shown that a finite magnetic moment ([mu][sub [nu]]) of the order of 10[sup [minus]10] in units of the Bohr magneton ([mu][sub [ital B]]) would modify the standard cooling curve of neutron stars for a period of 10--10[sup 3] yr after their birth, which demonstrates how crust cooling could compete with core cooling within the typical time scale for thermal conduction from the core to the surface. The consistency with the current observational data gives a limit [mu][sub [nu]][lt]5[times]10[sup [minus]7][mu][sub [ital B]] and possible improvements of this value in the future are discussed.

The neutrino mean free paths in hot neutron-star matter are obtained in the presence of kaon condensates. The kaon-induced neutrino absorption process, which is allowed only in the presence of kaon condensates, is considered for both nondegenerate and degenerate neutrinos. The neutrino mean free path due to this process is compared with that for the neutrino-nucleon scattering. While the mean free path for the kaon-induced neutrino absorption process is shown to be shorter than the ordinary two-nucleon absorption process by several orders of magnitude when temperature is not very high, the neutrino-nucleon scattering process has still a dominant contribution to the neutrino opacity. Thus, the kaon-induced neutrino absorption process has a minor effect on the thermal and dynamical evolution of protoneutron stars., 35 pages, 4 figures

The energy-loss rates of degenerate neutron-star matter due to thermal bremsstrahlung of pseudoscalar particles and axions via neutron-proton collisions together with the mean-free path and the energy spectrum from neutron-neutron, neutron-proton, and neutron-neutron processes are calculated. Analytic expressions for these quantities are obtained in the general case where the pseudoscalar particle couples to the proton and neutron with different strengths and the protons and the neutrons have different Fermi momenta. These rates are compared with those of other authors.

We investigate the thermal kaon process,in which kaons are thermally produced via nucleon-nucleon collisions.This process is relevant to nonequilibrium dynamics of kaon condensation inside neutron stars.The reaction rates for these processes are calculated, and their temperature and density dependences are compared with those of other reaction rates.It is shown that the thermal kaon process is dominant over other relevant weak reactions throughout the nonequilibrium process, such as the kaon-induced Urca and the modified Urca reactions, and may control the entire evolution of the kaon condensate. The characteristic role of the soft and hard kaons during the evolution is explained, and implications for astrophysical phenomena are briefly discussed., Comment: 31 pages,incl.10 eps figures,RevTeX

Emploi des donnees de Monte Carlo en fonctions de Green de Ceperley et Alder pour le facteur de forme statique, S(q), d'un liquide electronique, pour calculer la correction de champ electrique local, G(q), de la fonction dielectrique qui tient compte des correlations electroniques a courte distance. On utilise G(q) pour calculer les facteurs de forme statiques et dynamiques, la contribution a l'energie de correlation de differents transferts de moments, la dispersion des plasmons, et le coefficient de dispersion des plasmons

We calculate neutrino mean free paths from neutrino-neutron scattering in neutron matter. We formulate the problem such that the correlation effects of the neutron system can be taken into account in terms of Landau parameters. It is shown that the neutrinos are scattered not only by single-pair excitations (in the density and spin-density channels) but also by the collective mode of the system (spin-zero sound). We find that for degenerate neutrinos the effects of nucleon-nucleon interactions reduce the neutrino scattering rate by a factor 2-3, where the contribution from the collective mode is negligible because its temperature dependence is different from that of the single-pair excitations.

The equivalence of Pauli's ground-state-energy theorem and the virial theorem is demonstrated for a many-particle system interacting with an interparticle potential in d dimensions at zero and finite temperatures. Pauli's theorem has an integral form in which the variable is the coupling constant e-squared, while the virial theorem has a differential form in which the variable has the number density n. The essence of the equivalence proof consists in changing the variable from n to e-squared by noting the dependence of the excess free energy on dimensionless quantities for zero-temperature and classical cases.

The validity of the assumption that a chemical equilibrium is maintained during the quark beta decay reactions in degenerate quark matter is examined. If the decay mechanism is such that only the one-way reaction u+e/sup -/..-->..d+..nu../sub e/ is kinematically allowed without its inverse (d..-->..u+e/sup -/+nu-bar/sub e/), it drives the system away from the state of chemical beta equilibrium, eventually choking the reaction itself. By solving the kinetic equations which describe the time evolution of the chemical composition, it is shown that such a reaction is ineffective as a neutrino-emission mechanism for neutron-star cooling. In contrast to this, for a mechanism in which the decay proceeds in both directions, it is demonstrated that any perturbation in the chemical composition relaxes at an enhanced rate and chemical equilibrium is maintained thereafter.

The polarization-potential theory developed by Aldrich and Pines for helium liquids is extended to electron liquids. Configuration-space pseudopotentials are introduced to describe the modifications in electron interaction at short distances brought about by charge- and spin-induced correlations. The results obtained for the compressibility and spin susceptibility by Vosko, Wilk, and Nusair from Monte Carlo calculations are combined with simple physical arguments to obtain new expressions for the wave-vector-dependent dielectric function and spin susceptibility, which reduce in the long-wavelength limit to the Monte Carlo results. The relative effectiveness of charge- and spin-induced correlations is calculated as a function of electron density, and results are compared with previous calculations for electron liquids and with the corresponding results for the helium liquids.

It is shown that the beta decay of quarks in degenerate quark matter is kinematically allowed. The resulting neutrino emissivity is dramatically larger than that of neutron matter and comparable to that of matter with pion condensate. Thus a star with a quark-matter core would cool at a rate comparable to that for a star with a pion-condensed core, and much faster than an ordinary neutron star.

It is shown that axion emission from neutron stars is the dominant energy-loss mechanism for a range of values of the Peccei-Quinn symmetry-breaking scale (F) not excluded by previous constraints. This gives the possibility of obtaining a better bound on F from measurements of surface temperature of neutron stars.

The virial theorem is used to calculate the potential and kinetic energies of a paramagnetic electron liquid from the interpolation formulas for the correlation energy proposed by Wigner, by Nozi\`eres and Pines, and by Vosko, Wilk, and Nusair to check directly against the Monte Carlo data of Ceperley. The maximum errors for the potential energy from these formulas are found to be 29, 17, and 6 mRy, respectively, in the density range 1\ensuremath{\le}${r}_{s}$\ensuremath{\le}10.

The exact form of the third-frequency-moment sum rule is used to obtain the long-wavelength limit of the dynamic local-field correction of electron liquids within the formalism of Gross and Kohn. The effects of correlation modify the high-frequency behavior of the local-field correction typically by a factor 2--3 at metallic densities.