2-STEP PROCESSES AND SHORT-RANGE CORRELATIONS IN THE REACTION C-12(GAMMA,P)

One-nucleon knockout calculations have been performed for the reaction C12(,p)11B at incident photon energies of 60, 80, and 100 MeV. Both two-step processes and high-momentum components in the single-nucleon wave function due to short-range correlations have been included. It is shown that direct knockout leading to the B11 ground state followed by inelastic excitation of the 7/2- state at 6.743 MeV in B11 exceeds the direct excitation of this state by 1 to 2 orders of magnitude. For the ground-state transition the influence of high-momentum components becomes increasingly important going from E=60 to 100 MeV. Constraining the parameters entering the calculation by recently measured quasielastic C12(e,ep)11B data a discrepancy is found between the calculations and the data, particularly at low photon energies, which is attributed to exchange currents and random-phase approximation correlations. © 1990 The American Physical Society.