Comparison of measured neutron spectra with predictions of an intranuclear-cascade model
Abstract
Neutron spectra resulting from bombardment of targets of $^{48}\mathrm{Ca}$, $^{90}\mathrm{Zr}$, $^{120}\mathrm{Sn}$, and $^{208}\mathrm{Pb}$ with 45-MeV protons have been measured at many angles between 0\ifmmode^\circ\else\textdegree\fi{} and 160\ifmmode^\circ\else\textdegree\fi{}. Intranuclear-cascade, Monte Carlo calculations predict too many high-energy neutrons in the forward direction and too few neutrons, particularly high-energy neutrons, at angles greater than \ensuremath{\sim}45\ifmmode^\circ\else\textdegree\fi{}. Beyond 90\ifmmode^\circ\else\textdegree\fi{} the underprediction is by factors of 10 to 100. For angle-integrated spectra, however, there is reasonable agreement between theory and experiment.NUCLEAR REACTIONS $^{48}\mathrm{Ca}$, $^{90}\mathrm{Zr}$, $^{120}\mathrm{Sn}$, $^{208}\mathrm{Pb}(p,nx)$; $E=45$ MeV; measured $\ensuremath{\sigma}({E}_{n},\ensuremath{\theta})$ and $\ensuremath{\int}d\ensuremath{\Omega}\ensuremath{\sigma}({E}_{n},\ensuremath{\theta})$; enriched targets. Intranuclear-cascade model.