Levels and Transition Rates inMn53from theCr53(p,n)Mn53andCr53(p,nγ)Mn53Reactions

Differential cross sections of the ($p,n$) reactions have been measured as a function of angle at several proton energies from 2.6 to 5.9 MeV. Neutron groups corresponding to the ground and 21 excited levels have been observed, and excitation energies fixed to within ±5 keV in these measurements. The good agreement between the measured cross sections and those calculated in the Wolfenstein-Hauser-Feshbach (WHF) formalism for levels of known spin and the agreement between measured and calculated neutron angular distributions permitted tentative assignments to many levels of unknown spin. Angular distributions of the ($p,n\gamma$) transitions were measured at 4.9-MeV proton energy, with transitions from 19 excited levels observed. A decay scheme and excitation energies with ±2-keV uncertainty were obtained from the $\gamma$-ray measurements. Analysis of the angular distributions in the WHF formalism together with the neutron measurements provided the following excitation energies in keV and spin assignments: $2272$, $\frac{5}{2}$, $\frac{7}{2}$; $2405$, $\frac{3}{2}$; $2571$, ($\frac{7}{2}$); $2685$, $\frac{7}{2}$; $2949$, $\frac{9}{2}$; $3004$, ($\frac{3}{2}, \frac{5}{2}$); $3199$, $\frac{5}{2}$, $\frac{7}{2}$, $\frac{9}{2}$; $3248$, ($\frac{9}{2}$). Tentative assignments are in parentheses.