Δ-isobar production in proton-nucleus collisions

The ($\mathrm{p},\Delta$) reaction has been investigated in the general framework of the distorted-wave Born approximation. By the use of various choices for the spin-isospin transition interaction, $V_{\sigma \tau }(\mathrm{NN}\to \Delta \mathrm{N})$, it has been shown that the data on ${}_{}{}^6{}_{}{}^{}\mathrm{Li}(\mathrm{p},{\Delta }^{++}){}_{}{}^6{}_{}{}^{}\mathrm{He}$ at 1.04 GeV can be reproduced well, both in magnitude and shape, by the one-pion—and—one-rho—exchange potential. Using only the one-pion-exchange potential with the Landau-Migdal-type repulsive term it is found that the magnitude of the parameter $g_{\Delta }^{\prime }$ at high momentum transfer lies below 0.4.