Cross Section Measurements of Two-nucleon Pickup Reactions in the ¹³C+d System at Deuteron Energies below 350 keV

Cross sections of two-nucleon pickup reactions in the ¹³C+d system, i.e. ¹³C(d, α₀) ¹¹B and ¹³C(d, α₁)¹¹B* reactions have been measured for 180-350 keV deuterons. The angular distributions were measured in steps of 20 keV at 14 angles ranging from 30° to 164°, while the excitation functions were measured at 90° in steps of 10 keV. The excitation functions of ¹³C(d, α₀)¹¹B and ¹³C(d, α₁)¹¹B* reactions with 5-167 and 3-307 MeV Q-values, respectively, exhibit smooth variations of cross section with energy. The angular distribution of ¹³C(d, α₀)¹¹B reaction is asymmetric. With decreasing deuteron energy, the degree of asymmetry increases and below 220 keV deuteron energy the angular distribution is backward-peaked. This indicates a dominating contribution from the direct reaction in this channel below 220 keV deuteron energy. The angular distribution of ¹³C(d, α₁)¹¹B* reactions are highly symmetric about 90°, indicating a dominating compound nucleus contribution over this energy range. The trends of angular distribution of ¹³C(d, α₀)¹¹B and ¹³C(d, α₁)¹¹B* are consistent with the results of Putt (1971) at higher deuteron energies.