Parity violation in neutron-nucleus scattering

Parity violation is observed by measuring the helicity dependence of the neutron total cross section for low energy neutron resonances in heavy nuclei. The measurements are performed at the Los Alamos Neutron Scattering Center (LANSCE). Parity violation is a general feature of p-wave resonances. Our group has observed parity violations in {sup 81}Br, {sup 107,109}Ag, {sup 113}Cd, {sup 115}In, {sup 139}La, {sup 232}Th, and {sup 238}U. A statistical analysis is used to extract the effective neutron-nucleus rms parity violating matrix element.