Effects of proton correlations on the scattering of high-energy electrons from nuclei

Abstract

This paper investigates the extent to which the correlations between protons in nuclear matter manifest themselves in the scattering of high-energy electrons from nuclei. The infinite-order Born series is summed, so that dispersion effects that arise from excitation of virtual intermediate nuclear states are included to all orders. Use is made of a high-energy approximation developed earlier, and of the static or adiabatic approximation for the nuclear protons, and these are justified for incident electrons; their validity for nucleon scattering is also discussed. Expressions for the large-angle elastic and inelastic differential scattering cross-sections are obtained in this way. It is then shown that correlation effects are difficult to identify so long as the final nuclear state is well-defined. On the other hand, if a sum over final states is carried out, the effects of short-range correlations between protons appear in a characteristic way in the summed differential cross-section. These results are in qualitative agreement with those obtained earlier by others on the basis of the first and second Born approximation.