Cross sections forU238(n,n'γ)andU238(n,2nγ)reactions at incident neutron energies between 5 and 14 MeV

Abstract

Precision measurements of $^{238}\mathrm{U}$$(n,{n}^{'}\ensuremath{\gamma})$ and $^{238}\mathrm{U}$$(n,2n\ensuremath{\gamma})$ partial cross sections have been performed at Triangle Universities Nuclear Laboratory (TUNL) to improve crucial data needed for testing nuclear reaction models in the actinide mass region. A pulsed and monoenergetic neutron beam was used in combination with high-resolution \ensuremath{\gamma}-ray spectroscopy to obtain partial cross sections for incident neutron energies between 5 and 14 MeV. \ensuremath{\gamma}-ray yields were measured with high-purity germanium clover and planar detectors. Measured partial cross-section data are compared with previous results using white and monoenergetic neutron beams and calculations from the GNASH and TALYS Hauser-Feshbach statistical-model codes. Present experimental results are in fair to good agreement with most of the existing data for the $^{238}\mathrm{U}$$(n,{n}^{'}\ensuremath{\gamma})$ reaction. However, significant discrepancies are observed for the $^{238}\mathrm{U}$$(n,2n\ensuremath{\gamma})$ reaction.