Cross sections for the ($n,xp$), ($n,d$), and ($n,x\alpha$) reactions for 15-MeV neutrons on ${}_{}{}^{51}{}_{}{}^{}\mathrm{V}$ and ${}_{}{}^{93}{}_{}{}^{}\mathrm{Nb}$ have been measured with a magnetic quadrupole spectrometer. The importance of the ($n,n^{\prime }p$) reaction as a source of protons is examined by comparing these results with those recently obtained for ${}_{}{}^{46}{}_{}{}^{}\mathrm{Ti}$. Good fits to the ($n,xp$) and ($n,x\alpha$) energy spectra require contributions from both equilibrium and nonequilibrium reactions, while only the latter appear in the ($n,d$) spectra. Calculated values for the ($n,n^{\prime }p$) and ($n,n^{\prime }\alpha$) cross sections agree well with the experimental values. The cross sections are ${}_{}{}^{51}{}_{}{}^{}\mathrm{V}\mathrm{}(n,xp)\mathrm{}$ 91 ± 14 mb, ${}_{}{}^{51}{}_{}{}^{}\mathrm{V}\mathrm{}(n,xd)\mathrm{}$ 7 ± 3 mb, ${}_{}{}^{51}{}_{}{}^{}\mathrm{V}(n,x\alpha )$ 17 ± 3 mb, ${}_{}{}^{93}{}_{}{}^{}\mathrm{Nb}\mathrm{}(n,xp)\mathrm{}$ 51 ± 8 mb, ${}_{}{}^{93}{}_{}{}^{}\mathrm{Nb}\mathrm{}(n,xd)\mathrm{}$ 8 ± 3 mb, and ${}_{}{}^{93}{}_{}{}^{}\mathrm{Nb}(n,x\alpha )$ 14 ± 3 mb.

[NUCLEAR REACTIONS ${}_{}{}^{51}{}_{}{}^{}\mathrm{V}\mathrm{}(n,xp)\mathrm{}$, ${}_{}{}^{51}{}_{}{}^{}\mathrm{V}\mathrm{}(n,xd)\mathrm{}$, ${}_{}{}^{51}{}_{}{}^{}\mathrm{V}(n,x\alpha )$, ${}_{}{}^{93}{}_{}{}^{}\mathrm{Nb}\mathrm{}(n,xp)\mathrm{}$, ${}_{}{}^{93}{}_{}{}^{}\mathrm{Nb}\mathrm{}(n,xd)\mathrm{}$, ${}_{}{}^{93}{}_{}{}^{}\mathrm{Nb}(n,x\alpha )$, $E_n=14.8\mathrm{}$ MeV, measured $\sigma (E_p,\theta )$, $\sigma (E_d,\theta )$, $\sigma (E_{\alpha },\theta )$, Hauser-Fesh-bach analysis; deduced reaction mechanism.]

• Received 19 July 1977

DOI:https://doi.org/10.1103/PhysRevC.17.508