Bulk viscosity of magnetized neutron star matter

We study the effect of a magnetic field on the bull; viscosity of nuclear m atter in neutron stars. We employ the framework of relativistic mean-field theory to model the dense nuclear matter in neutron stars. The effects are first studied for the case when the magnetic field does not exceed the crit ical, value to confine the electrons to the lowest Landau levels. We then c onsider the case of an intense magnetic held to evaluate the viscosity for the URCA processes and show that the inequality p(F)(e) + p(F)(p) greater t han or equal to p(F)(n) is no longer required to be satisfied for the URCA processes to proceed.