Finite-nucleus treatment of the response to sigmaμτλprobes and pion-like excitations. II. The role of rho-meson exchange

Abstract

For pt.I see ibid., vol.10, p.1347, 1984. The author presents an exact finite-nucleus study of the effect of the rho -meson-exchange piece of the particle-hole interaction on the response to spin-isospin-sensitive ( sigma mu tau lambda ) probes. He studies the nuclear response for various forms of the effective rho exchange interaction for a large range of momentum transfer (q approximately 0-600 MeV/c). The renormalisation of matrix elements of spin-isospin-sensitive probes ( sigma mu tau lambda ) is given for the JP=1+, T=1 level of 12C. The exact results are compared with calculations based on infinite nuclear matter with a constant density of rho =0.17 fm-3 and rho =0.07 fm-3. He also compares with local-density-approximation results using three different density distributions (square well, Fermi and modified harmonic oscillator). All these approximate calculations are found to be unsatisfactory in describing the finite-nucleus features and the effect of the rho meson itself.