Probing the shell model using nucleon knockout reactions

We assess the sensitivity of the intermediate energy, direct two-nucleon knockout reaction mechanism to details of the correlated motions of the two removed nucleons as might be revealed by measurements of partial cross sections to different final states of the mass A−2 reaction residues. Comparisons of new reaction calculations with recent data for exotic nuclei in the sd-shell suggest that this sensitivity is significant and that the coherence of the twonucleon configurations to the reaction allows small wave function components to be probed. The relative yields for the different J transitions are well described by the USD shell model calculations, however the measured cross sections require an overall suppression of the shell model two-nucleon spectroscopic strengths.