Evidence for sequential two-body decay in the C 12(d; p, n)C 12 reaction

Abstract

The C 12(d; p, n) reaction has been studied using the Rice University high resolution 180° magnetic spectrometer for deuteron energies of 4.66, 4.90 and 5.46 MeV. No evidence was found for the existence of a density of states cusp near the neutron threshold similar to that seen in the Be 9(p; p′, n)Be 8 reaction studied by Spencer et al. 1). However, broad proton groups were observed at energies which correspond to the two-body sequential decay C 12+ d→ N 14∗→ N 13∗ + n→ C 12+ n+ p . Two excited states in N 13 involved in this were the known 3.51 and 3.56 MeV states. The proton groups show broadening and energy shifting due to the motion of the intermediate N 13 nucleus. Theoretical line shapes have been calculated to compare with these data. The groups occur at proton energies of approximately 1.01, 1.04 and 1.08 MeV, with each broad group possesing a doublet structure with approximate widths at half height of 60, 50 and 90 keV corresponding to the deuteron bombarding energies of 4.66, 4.90 and 5.46 MeV respectively. No evidence for states at 5.51 and 6.10 MeV in C 13 was observed.