2.335-MeV Isobaric Analog Resonance inV51+pand the Excited States ofCr51Studied via the (p,n) and (p,nγ) Reactions

The 2.335-MeV isobaric analog resonance in ${}_{}{}^{51}{}_{}{}^{}\mathrm{V}\mathrm{}(p,n)\mathrm{}{}_{}{}^{51}{}_{}{}^{}\mathrm{Cr}$ and ${}_{}{}^{51}{}_{}{}^{}\mathrm{V}\mathrm{}(p,p)\mathrm{}{}_{}{}^{51}{}_{}{}^{}\mathrm{V}$ was studied experimentally. Detailed analysis was not possible because of the complexity of the excitation function in this energy region. ${}_{}{}^{51}{}_{}{}^{}\mathrm{V}\mathrm{}(p,n)\mathrm{}{}_{}{}^{51}{}_{}{}^{}\mathrm{Cr}$ angular distributions at 4.013- and 5.016-MeV bombarding energies were analyzed via statistical-model formalism. 12 states in ${}_{}{}^{51}{}_{}{}^{}\mathrm{Cr}$ were observed up to an excitation energy of 2.39 MeV. The $\gamma$ rays from the transitions (777→749 keV) and (749 keV → ground state) have been observed and their angular distributions determined to be isotropic. Angular distributions of the 1165-, 1480-, and 2001-keV $\gamma$ rays leading to the ground state of ${}_{}{}^{51}{}_{}{}^{}\mathrm{Cr}$ have been measured at proton bombarding energies of 4.0 and 4.4 MeV. Spins of ${\frac{9}{2}}^{-}$ and ${\frac{11}{2}}^{-}$ are assigned to the 1165- and the 1480-keV levels, respectively, in agreement with other investigators. The angular distribution for the 2001-keV level is isotropic indicating a spin of $\frac{7}{2}$ or less. Higher excited states in ${}_{}{}^{51}{}_{}{}^{}\mathrm{Cr}$ were observed through the ($p,n$) reaction at 2256, 2313, and 2380 keV. The ($p,n$) yield coupled with the failure to observe the ground-state transition from the 2256-keV level in the $\gamma$-ray spectra indicates that the spin of this level is greater than $\frac{13}{2}$.