The Delta(1232)-nucleon interaction in the 2H(p,n) charge exchange reaction

Abstract

The 2H(p,n) charge exchange reaction at T_p=790 MeV is used to study the Delta(1232)-nucleon interaction in the Delta resonance excitation energy region. For the Delta-N potential, a meson exchange model is adopted where pi, rho, omega, and sigma meson exchanges are taken into account. The deuteron disintegration below and above pion threshold is calculated using a coupled channel approach. Various observables, such as the inclusive cross section, the quasifree Delta decay, the coherent pion production, and the two-nucleon breakup are considered. It is shown that these observables are influenced by the dynamical treatment of the Delta degrees of freedom. Of special interest is the coherent pion decay of the Delta resonance which is studied by means of the exclusive reaction 2H(p,n pi+)2H. Both the peak energy and the magnitude of the coherent pion production cross section depend very sensitively on the strength of the Delta-N potential. The coherent pions have a peak energy of 300 MeV and a strongly forward peaked angular distribution.