Inclusive 150-MeV-proton-induced spectra at forward angles

Inclusive proton spectra were measured from the interaction of 150 MeV protons with a variety of targets ranging from berylium to bismuth over the angular range from 10° to 30°. At all of the angles at which data were taken the spectra from the berylium and the carbon targets show strong peaks attributable to quasifree scattering while the spectra from nickel and heavier targets are rather flat throughout the continuum region. The quasifree scattering is calculated using a Fermi gas model, with the nucleus a uniform sphere, and in this picture the required attenuation of a quasifree peak requires a nucleon free path of no more than about 3.5 fm. Spectra of deuterons, tritons, ${}_{}{}^3{}_{}{}^{}\mathrm{He}$, and alpha particles were also measured.