Fermi hypernetted-chain calculation of the half-diagonal two-body density matrix of model nuclear matter

Abstract

The half-diagonal two-body density matrix ρ2h(r1,r2,r1′) is a key quantity in theoretical descriptions of nucleon knockout reactions at intermediate energies, due to its central role in treatments of the propagation and final-state interactions of ejected nucleons in the nuclear medium. This quantity is calculated for a simple model of the ground state of infinite symmetrical nuclear matter, based on a Jastrow-correlated wave function and a Fermi hypernetted-chain analysis. The dependence of ρ2h on the variables r11′=|r1−r1′|, r12=|r1−r2|, and the angle θ between r1−r1′ and r1−r2 is investigated in some detail. Significant departures from ideal Fermi gas behavior in certain domains reflect the importance of short-range correlations and their interplay with statistical correlations. The quality of approximations to ρ2h proposed by Gersch et al., Rinat, and Silver is assessed by comparison with the Fermi hypernetted-chain results.