Importance of the deuteron quadrupole moment in sup2H(d,)4He

We present a phenomenological study of the H2(d,) 4He reaction that allows for the D-state component of the colliding deuterons. The low-energy cross section is determined by an interference between E2 transitions from an initial S25 scattering state to either the D- or S-state components of He4, the latter via the internal quadrupole moment of the deuteron. From a fit to the data, we determine the asymptotic D/S ratio of He4 to be -0.40.