Cumulative Parity Violation in Supernovae

Supernovae provide a unique opportunity for large scale parity violation because they are dominated by neutrinos. We calculate the parity violating asymmetry A of neutrino emission in a strong magnetic field. We assume the neutrinos elastically scatter many times from slightly polarized neutrons. Because of multple interactions, A grows with the optical thickness of the proto-neutron star and may be much larger than previous estimates. As a result, the neutron star could recoil at a significant velocity.