ELECTRICAL-CONDUCTIVITY OF NEUTRON-STAR CORES IN THE PRESENCE OF STRONG MAGNETIC-FIELDS - EFFECTS OF INTERACTIONS AND SUPERFLUIDITY OF NUCLEONS

The electric resistivity tensor of npe-matter in the cores of neutron stars with magnetic field B is calculated for the case when the protons are nonsuperfluid and the neutrons are either normal or superfluid due to the singlet-state pairing. The tensor contains the longitudinal, transverse and Hall resistivities, R parallel-to, R perpendicular-to, and R(H). Their explicit expressions are obtained for densities rho-around the standard nuclear matter density rho = 2.8 x 10(14) g.cm-3 in terms of nucleon Fermi momenta and effective masses renormalized due to medium effects. R parallel-to is equal to the field-free resistivity R0, R(H) is-proportional-to B; neither of them depends on the neutron superfluidity. R perpendicular-to = R0 + R(B) contains the term R(B) is-proportional-to B2 which can greatly enhance R perpendicular-to, if B is strong. When T greater-than-or-equal-to T(c), R(B) scales as T-2. If 0.2 T(c) less-than-or-similar-to T < T(c), R(B) becomes larger than its nonsuperfluid value. At lower T, on the contrary, R(B) is greatly suppressed by the superfluidity. These results can be used to study the cooling rates of neutron stars with large internal magnetic fields.