Parity Nonconservation in Neutron Resonances in 133Cs
Copyright held by American Physical Society. First published as EI Sharapov et al, Parity Nonconservation in Neutron Resonances in 133Cs, Physical Review C, 59:3, 1772–1779, doi: 10.1103/PhysRevC.59.1772.
Spatial parity nonconservation (PNC) has been studied in the compound-nuclear states of 134Cs by measuring the helicity dependence of the neutron total cross section. Transmission measurements on a thick 133Cs target were performed by the time-of-flight method at the Manuel Lujan Neutron Scattering Center with a longitudinally polarized neutron beam in the energy range from 5 to 400 eV. A total of 28 new p-wave resonances were found, their neutron widths determined, and the PNC longitudinal asymmetries of the resonance cross sections measured. The value obtained for the root-mean-square PNC element M=(0.06-0.02+0.25) meV in 133Cs is the smallest among all targets studied. This value corresponds to a weak spreading width Γw=(0.006-0.003+0.154)×10-7 eV.