Absolute cross sections and isomeric cross-section ratios for theNd148(d,2n),Nd148(p,n), andNd146(α,pn)reactions producing the isomeric pairPmm,g148

Abstract

Excitation functions and isomeric cross-section ratios were determined for the $^{148}\mathrm{Nd}(d,2n)$, $^{148}\mathrm{Nd}(p,n)$, and $^{146}\mathrm{Nd}(\ensuremath{\alpha},pn)$ reactions producing the isomeric pair $^{148}\mathrm{Pm}^{m,g}$. The experimental isomer ratios of 41.3-day $^{148}\mathrm{Pm}^{m}$ (6-) and 5.37-day $^{148}\mathrm{Pm}^{g}$ (1-) were compared with statistical model calculations wherein spin cutoff parameters $\ensuremath{\mu}$ were obtained assuming that $\ensuremath{\sigma}$ is either independent or varying with excitation energy. The spin cutoff parameters and the effective moments of inertia deduced from these calculations were $\ensuremath{\sigma}=4.2$ and $\ensuremath{\theta}=0.70{\ensuremath{\theta}}_{r}$, respectively, for the reaction $^{148}\mathrm{Nd}(p,n) ^{148}\mathrm{Pm}^{m,g}$, and $\ensuremath{\sigma}=3.9$ and $\ensuremath{\theta}=0.65{\ensuremath{\theta}}_{r}$, respectively, for the reaction $^{148}\mathrm{Nd}(d,2n) ^{148}\mathrm{Pm}^{m,g}$.[NUCLEAR REACTIONS $^{148}\mathrm{Nd}(p,n)$, ($d,2n$), $^{146}\mathrm{Nd}(\ensuremath{\alpha},pn)$, ${E}_{P}=9\ensuremath{-}45$ MeV, ${E}_{d}=6.5\ensuremath{-}52$ MeV, ${E}_{\ensuremath{\alpha}}=29\ensuremath{-}59$ MeV; measured $\ensuremath{\sigma}(E)$, isomer ratio; deduced spin cutoff parameter, moment of inertia.]