A MEASUREMENT OF 12C(P,2P) REACTION AT 385 MEV WITH GOOD MOMENTUM RESOLUTION

A method of measuring absolute values of (p, 2p) reaction cross sections at 385 MeV has been developed which uses wide range magnetic spectrometers. The measurements made on 12C(p, 2p) provide new evidence supporting the interpretation of the cross section in terms of a spectator model. This interpretation gives an estimate of the momentum distribution of the protons bound in 12C and the results show that the effect of distortion of the ingoing and outgoing proton waves is to reduce the magnitude measured for the momentum distribution but not to change its shape. We find the magnitude of the peak of the p state distorted momentum distribution to be 0.27±0.03 fm3, a result not in agreement with previous measurements. The resolution in momentum space is sufficient to resolve the minimum of the p state distorted momentum distribution and we find that there is no conflict with the theoretical predictions of the depth of this minimum. © 1969.