Production of E1 Radiation in the ²H(d, Υ)⁴He Reaction at Very Low Energies

Abstract.

An argument is given that the mechanism of charge polarization cannot give rise to E1 radiation in the ²H(d, Υ)⁴He reaction. It then follows that E1 radiation produced in this reaction probably arises from the spin-dependent part of the E1 operator, although small E1 admixtures have been shown to arise in coupled-channels calculations as a result of Coulomb-induced isospin mixing in ³H and ³He. A proper calculation of this reaction should consider mesonexchange currents and remains to be performed.