Excitation functions for 12 nuclear reactions of type ${}_{}{}^{90}{}_{}{}^{}\mathrm{Zr}\mathrm{}\left[\right(p,(2-4\mathrm{})p,\mathrm{}(1-6)n]$ have been measured for incident proton energies from 10-86 MeV. The complex excitation functions have been decomposed to yield a component due to emission of one or two $\alpha$ particles, and a component due to the emission of individual nucleons. Combining the $\alpha$ particle portions of the decomposed excitation functions, the excitation energy spectra for those events associated with $\alpha$ particle emission have been derived. Having estimated the excitation functions for a few missing reactions, the total probability of emission of seven combinations of charged particles as a function of incident proton energy has been calculated. The implications of the results on the preequilibrium model of nuclear reactions are discussed.

NUCLEAR REACTIONS ${}_{}{}^{90}{}_{}{}^{}\mathrm{Zr}(p,ypxn)$, $y=2-4\mathrm{}$, $x=1-6\mathrm{}$, $E=10-86\mathrm{}$ MeV; measured $\sigma \mathrm{}\left(E\right)\mathrm{}$; deduced $\alpha$; particle yields, charged-particle emission probabilities. Enriched target.

• Received 11 February 1976

DOI:https://doi.org/10.1103/PhysRevC.14.64