The ${}_{}{}^{12}{}_{}{}^{}\mathrm{C}$(n,p${)}^{12}$B reaction was studied using the white neutron source at the Los Alamos Meson Physics Facility/Weapon Neutron Research Center with a continuous incident neutron energy from 60 to 260 MeV. Double differential cross sections were measured in the angular range 11°≤${\mathrm{\theta }}_{\mathrm{lab}}$≤37°. Using the neutron time-of-flight facility at the Indiana University Cyclotron Facility, we also studied the ${}_{}{}^{12}{}_{}{}^{}\mathrm{C}$(p,n${)}^{12}$N reaction at ${\mathit{E}}_{\mathit{p}}$=186 MeV and the ${}_{}{}^{12}{}_{}{}^{}\mathrm{C}$(p→,n→${)}^{12}$N reaction at ${\mathit{E}}_{\mathit{p}\to }$=160 and 186 MeV. Double differential cross sections were measured between ${\mathrm{\theta }}_{\mathrm{lab}}$=0° and ${\mathrm{\theta }}_{\mathrm{lab}}$=50° in 5° steps. Spin observables ${\mathit{D}}_{\mathit{N}\mathit{N}}$, ${\mathit{A}}_{\mathit{Y}}$, and P were measured at ${\mathrm{\theta }}_{\mathrm{lab}}$=5°,9°,13° with ${\mathit{E}}_{\mathit{p}\to }$=160 MeV and ${\mathrm{\theta }}_{\mathrm{lab}}$=15°,20° with ${\mathit{E}}_{\mathit{p}\to }$=186 MeV. Angular distributions of differential cross section and spin observables for low-lying transitions in the residual nuclei are compared with disorted-wave impulse approximation (DWIA) calculations. A multipole decomposition analysis was performed to study the giant dipole and giant spin-dipole resonances. The contributions of the quasifree reaction in the giant resonance region was subtracted. The empirical results of energy distributions for dipole (ΔL=1) transition are compared with DWIA calculations using nuclear structure information obtained with a conventional shell model and also with a random phase approximation.

• Received 29 March 1993

DOI:https://doi.org/10.1103/PhysRevC.48.1158