On the nuclear direct photodisintegration

The individual-particle shell model is used in order to describe the initial and final nuclear states which are involved in the nuclear direct photodisintegration. General formulae for the final statistical matrix are deduced in the case of initially polarized nuclei and polarized photons. These results are expressed in the extreme j-j as well as in the extreme L-S coupling scheme. Some reasonable limiting assumptions are made with the aim of pointing out how the angular correlations depend on the coupling scheme. The first p-shell is considered in detail; we find that the cross-section depends remarkably on the coupling scheme, and that the polarization can change its sign in addition to its value.