Angular distribution of gamma rays from a neutron-induced p-wave resonance of 132Xe

A neutron-energy dependent angular distribution was measured for individual gamma rays from the 3.2 eV p -wave resonance of 131Xe +n, that shows enhanced parity violation owing to a mixing between s- and p-wave amplitudes. The gamma-ray transitions from the p-wave resonance were identified, and the angular distribution with respect to the neutron momentum was evaluated as a function of the neutron energy for 7132 keV gamma rays, which correspond to a transition to the 1807 keV excited state of 132Xe. The angular distribution is considered to originate from the interference between s- and p-wave amplitudes, and will provide a basis for a quantitative understanding of the enhancement mechanism of the fundamental parity violation in compound nuclei.