Microscopic study of the 2H(α, γ)6Li reaction in a multicluster model

We use the generator coordinate method (GCM) to define multicluster wave functions of the α + (p + n) system. Distortion effects of the deuteron are included through a mixing of several p + n configurations. The model is tested on the 6Li spectroscopy, and on the a+ p and a + d elastic phase shifts. The comparison with experiment gives a fairly good agreement in all the cases. At low temperatures, we predict a reduction by a factor of 10 of the 2H(α, γ)6Li reaction rate, with respect to astrophysics compilations. The GCM cross section is also used to test the validity of the extranuclear approximation.