Scattering of Protons fromC12in the Energy Range of 5-6 MeV

Abstract

Excitation functions and angular distributions were obtained in the bombarding energy range 5-6 MeV for the elastic and inelastic (4.43-MeV state) scattering of protons from ${\mathrm{C}}^{12}$, for the 4.43-MeV gamma rays. Three resonances were observed, at bombarding energies of 5.38, 5.68, and 5.90 MeV (excitation energies in ${\mathrm{N}}^{13}$ of 6.91, 7.19, and 7.40 MeV). The corresponding center-of-mass widths are 115±5 keV, 9±0.5 keV, and 75±5 keV, respectively. The center-of-mass elastic widths are 4.6, 0.36, and 6.9 keV, respectively. Analysis of the interference characteristics of the elastic scattering cross sections, together with analysis of the various angular distributions and applications of the Wigner limit rule, leads to the following assignments of quantum numbers: for the 5.38-MeV (bombarding energy) resonance, $\frac{3}{2^{+}}$; for the 5.68-MeV resonance, very probably $\frac{7}{2^{+}}$; for the 5.90-MeV resonance, $\frac{5}{2^{-}}$.