Light-Particle Spectra from the Nitrogen Bombardment of Oxygen

Abstract

Energy spectra and angular distributions were measured for protons and $\alpha$ particles resulting from the nitrogen bombardment of oxygen. It was found that the angular distributions of protons are reasonably isotropic whereas $\alpha$ particles are peaked in the forward direction. The energy distributions at various angles were compared with the predictions of a simple level density formula $w=C\exp \left[2\mathrm{}{\left(a{E}^{*}\right)}^{\frac{1}{2}}\right]$. The constant $a$ was found to be $a=2.5\mathrm{}\pm 0.2$ from proton spectra, $a=1.3\mathrm{}\pm 0.2$ from $\alpha$-particle spectra at all angles measured. The energy spectrum of deuterons was measured at 15 deg and a value of $a=1.8\mathrm{}\pm 0.3$ was found. Unexplained structure was observed in the spectrum of $\alpha$ particles emitted at zero degrees. After correction for the phase space available and the barrier penetration, it was found that $\alpha$ particles are emitted on the order of ten times more copiously than protons, while deuterons are about half as abundant as protons.