Determination of the level density of 29Si from Ericson fluctuations.

Abstract

Neutron total cross-section measurements for $^{28}\mathrm{Si}$ have been made with the white neutron source at Los Alamos Meson Physics Facility for neutron energies between 4 and 600 MeV. Very good resolution (\ensuremath{\approxeq}0.2 ns/m) was obtained. The detailed structure at low energies is found to be different than obtained in previous measurements, although at energies 7${\mathit{E}}_{\mathit{n}}$15 MeV the agreement is quite good. The cross section becomes quite smooth above 15 MeV. An Ericson analysis is performed to yield values for the level density of $^{29}\mathrm{Si}$ between 13 and 22 MeV.