Spin form factors of A = 3 nuclei and excitation of the nuclear pion modes through the (3He,t) reaction

Matrix elements of the spin-isospin operators have been computed between Faddeev wavefunctions of the A=3 nuclei, incorporating the ρ- and π-mesons exchange contributions. The corresponding form factors at the 3He-t vertices are evaluated and used as input in a free-parameter calculation of the cross sections for the reaction p(3He, t)Δ++. The results agree with experimental data, giving more support to the sensitivity of (3He, t) reactions to the nuclear pionic mode. (orig.)