Relativistic mean-field treatment of pulsar kicks from neutrino propagation in magnetized proto-neutron stars

We make a perturbative calculation of neutrino scattering and absorption in hot and dense hyperonic neutron-star matter in the presence of a strong magnetic field. We calculate that the absorption cross-sections in a fully relativistic mean-field theory. We find that there is a remarkable angular dependence, i.e., the neutrino absorption strength is reduced in a direction parallel to the magnetic field and enhanced in the opposite direction. This asymmetry in the neutrino absorption is estimated to be as much as 2.2% of the entire neutrino momentum for an interior magnetic field of ∼2×1017G. The pulsar kick velocities associated with this asymmetry are shown to be comparable to observed velocities.