Effect of breakup on the deuteron nucleus spin orbit and tensor potentials

Abstract

A previous treatment of breakup in terms of a coupled channel formulation is generalized so as to include the spin of the nucleus. The break up spectrum is described in terms of the eigenstates of the free neutron proton Hamiltonian, based on the Reid soft core potential. Nearly spherically symmetric as well as nearly quadrupole deformed break up states are included. The latter give large contributions to the correction to the spin orbit and tensor parts of the deuteron-nucleus elastic optical model. A numerical application for 13 MeV and 21.6 MeV deuterons incident on Ni is presented, in which virtual breakup is included to second order in the breakup transition matrix element. The breakup correction to the deuteron potential is strongly dependent on the orbital angular momentum and the energy of the deuteron-nucleus motion. The spin orbit potential is rendered less diffuse and acquires an imaginary part. The tensor potential correction is comparable in radial shape to the Watanabe static folding model result, and tends to increase its magnitude by nearly 100%.