H2(d→,γ)4He reaction atEd=95 MeV

The tensor analyzing power A/sub y//sub y/(theta), vector analyzing power A/sub y/(theta), and cross section sigma(theta) of the /sup 2/H(d-italic-arrow-right,..gamma..)/sup 4/He reaction have been measured for the angular range of 55/sup 0/--149/sup 0/ in the center of mass system at an incident deuteron energy of 95 MeV. The reaction is dominated by the transition involving the S-state component of /sup 4/He, as indicated by the approximately sin/sup 2/2theta angular distribution of the cross section. The observed deviation of sigma(theta) from this shape is due to either M2 strength, tensor force effects, or both. The tensor analyzing power A/sub y//sub y/(theta) is nearly isotropic, with a typical value of approximately 0.3 +- 0.1. The vector analyzing power A/sub y/ is zero within the statistical precision (typically +- 0.2) of this data set, indicating a reduced contribution from E1 and M2 transitions compared to lower energies. Direct capture calculations in the plane-wave Born approximation do not reproduce even the sign of A/sub y//sub y/.