Neutron nonelastic collision cross sections for eleven elements have been measured in the energy range 21-29 Mev. Corrections were applied to the data by means of a UNIVAC calculation. Since no experimental neutron angular distributions are available in this energy region, optical-model calculations were used for the correction problem. In general the cross sections at 25 Mev are 10% to 20% lower than at 14 Mev.

• Received 16 April 1958

DOI:https://doi.org/10.1103/PhysRev.111.1155