Shell and odd-even effects in preequilibrium (p,p') and (n,n') processes

We have systematically measured energy spectra of protons emitted from 18 MeV (p,xp) reactions on 90Zr, 93Nb, 92,94,96,98,100Mo, 106Pd, and Ag, and of neutrons emitted from 14.1 MeV (n,xn) reactions on Ag, Cd, In, Sn, Sb, and Te in order to investigate the shell and odd-even effects in the preequilibrium (p,p') and (n,n') processes. It was found that there are no appreciable shell and odd-even effects in the preequilibrium (p,p') and (n,n') spectra corresponding to excitations above 4 MeV of the residual nuclei. The experimental results were reasonably interpreted using the state densities derived from realistic single particle levels introducing a shell gap. The effect of the direct process in continuum spectrum region was also examined in terms of collective excitations of the low energy octupole resonance(LEOR). (author)