Interaction of Neutrons with Oxygen and a Study of theC13(α, n)O16Reaction

Abstract

Measurements of the oxygen total neutron cross section from 3.5 to 4.4 Mev and the ${\mathrm{O}}^{16}(n, \alpha ){\mathrm{C}}^{13}$ reaction cross section from 4.0 to 5.2 Mev are presented. In a study of the ${\mathrm{C}}^{13}(\alpha , n){\mathrm{O}}^{16}$ reaction the following quantities were measured: the 0° yield from 0.8 to 3.5 Mev, 29° and 146° yields between 2.0 and 3.5 Mev, and 47 angular distributions in the range from 1.0 to 3.5 Mev. Cross sections for the ${\mathrm{O}}^{16}(n, \alpha ){\mathrm{C}}^{13}$ and the ${\mathrm{C}}^{13}(\alpha , n){\mathrm{O}}^{16}$ reactions are compared using the principle of detailed balancing. On the basis of the ${\mathrm{C}}^{13}(\alpha , n)$ angular distributions spin assignments for 14 states of ${\mathrm{O}}^{17}$ between excitation energies 7 and 9 Mev are discussed, and in some cases relative parity assignments are made. Reduced widths of the states of ${\mathrm{O}}^{17}$ were derived from the results of the experiments on the ${\mathrm{C}}^{13}(\alpha , n)$ reaction and the oxygen total neutron cross section.