The 2 H(p, n) charge exchange reaction at Tp = 790 MeV is used to study the ∆(1232)-nucleon (∆N ) interaction in the ∆ resonance excitation energy region. For the ∆N potential, a meson exchange model is adopted where π, ρ, ω, and σ 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 ∆ 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 ∆ degrees of freedom. Of special interest is the coherent pion decay of the ∆ resonance which is studied by means of the exclusive reaction 2 H(p, nπ + ) 2 H. Both the peak energy and the magnitude of the coherent pion production cross section depend very sensitively on the strength of the ∆N potential. The coherent pions have a peak energy of ω = 300 MeV and a strongly forward peaked angular distribution.

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The inclusive 2 H( 3 He,t) reaction has been studied at 2 GeV for energy transfers up to 500 MeV and scattering angles from 0.25 0 up to 4 0 . Data are well reproduced by a model based on a coupled-channel approach for describing the NN and N∆ systems. The effect of final state interaction is important in the low energy part of the spectra. In the delta region, the cross-section is very sensitive to the effects of ∆-N interaction and ∆N → NN process. The latter has also a large influence well below the pion threshold. The calculation underestimates the experimental cross-section between the quasi-elastic and the delta peaks; this is possibly due to projectile excitation or purely mesonic exchange currents.PACS. 25.55.Kr 2 H-, 3 He-and 4 He-induced charge exchange reactions -14.20.Gk Baryon resonances with S=0 -24.10.Eq Coupled channel and distorted wave models

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