Proton and deuteron inelastic excitation of the 1/sup +/ state at E/sub x/ = 5. 846 MeV in /sup 208/Pb: Isoscalar character and importance of tensor correlations

Differential cross sections for /sup 208/Pb(p,p') and /sup 208/Pb(d,d') excitation of the 1/sup +/ state at E/sub x/ = 5.846 MeV were measured at E/sub inc/ = 45 MeV. The fact that the measured strengths of both reactions are very similar supports the isoscalar nature of the 1/sup +/ state. The comparison of the experimental proton angular distribution to microscopic distorted-wave calculations using random phase approximation wave functions with and without tensor correlations suggests that the isoscalar tensor part of the (..pi..+rho)-exchange potential is too strong.