Proton-proton elastic scattering via the Trojan horse method

We address a successful indirect technique, the Trojan horse method, which allows one to measure the bare nucleus cross section for rearrangement reactions down to astrophysical energies. In particular, we consider here the application of the method to the p - p elastic scattering. This represents an important test of the main feature of the method, namely the suppression of Coulomb effects in the entrance channel due to off-energy-shell effects. In contrast to the on-energy-shell case, the extracted p - p cross section does not exhibit the Coulomb-nuclear interference minimum, as predicted by the half-off-energy shell calculations. This hypothesis is strengthened by the agreement between the Trojan horse p - p data and the calculated on-energy-shell n - n , n - p and nuclear p - p cross sections.