One-body density matrix and momentum distribution in s-p and s-d shell nuclei

Abstract

Analytical expressions of the one- and two- body terms in the cluster expansion of the one-body density matrix and momentum distribution of the s-p and s-d shell nuclei with N=Z are derived. They depend on the harmonic oscillator parameter b and the parameter $\beta$ which originates from the Jastrow correlation function. These parameters have been determined by least squares fit to the experimental charge form factors. The inclusion of short-range correlations increases the high momentum component of the momentum distribution, $n({\bf k})$ for all nuclei we have considered while there is an A dependence of $n({\bf k})$ both at small values of k and the high momentum component. The A dependence of the high momentum component of $n({\bf k})$ becomes quite small when the nuclei $^{24}$Mg, $^{28}$Si and $^{32}$S are treated as 1d-2s shell nuclei having the occupation probability of the 2s-state as an extra free parameter in the fit to the form factors.