Cross section measurements of two-nucleon pickup reactions in the C-13+d system at deuteron energies below 350 keV

Cross sections of two-nucleon pickup reactions in the C-13+d system, i.e. C -13(d, alpha(0))B-11 and C-13(d, alpha(1))B-11* reactions have been measure d for 180-350 keV deuterons. The angular distributions were measured in ste ps of 20 keV at 14 angles ranging from 30 degrees to 164 degrees, while the excitation functions were measured at 90 degrees in steps of 10 keV. The e xcitation functions of C-13(d, alpha(0))B-11 and C-13(d, alpha(1))B-11* rea ctions with 5.167 and 3.307 MeV Q-values, respectively, exhibit smooth vari ations of cross section with energy. The angular distribution of C-13(d, al pha(0))B-11 reaction is asymmetric. With decreasing deuteron energy, the de gree of asymmetry increases and below 220 keV deuteron energy the angular d istribution is backward-peaked. This indicates a dominating contribution fr om the direct reaction in this channel below 220 keV deuteron energy. The a ngular distribution of 13C(d, alpha(1))B-11* reactions are highly symmetric about 90 degrees, indicating a dominating compound nucleus contribution ov er this energy range. The trends of angular distribution of C-13(d, alpha(0 ))B-11 and C-13(d, alpha(1))B-11* are consistent with the results of Putt ( 1971) at higher deuteron energies.