THE CHARGE RESPONSE OF A MESON-CORRELATED RELATIVISTIC FERMI GAS

The quasielastic longitudinal electromagnetic response function R(L) i s studied within the context of the relativistic Fermi gas model exten ding our previous investigations, which only included pionic correlati ons and currents. Four mesons are now employed (pi, rho, sigma and ome ga, via the Bonn potential) and the many-body dynamics are extended to the full antisymmetrized random-phase approximation built upon a Hart ree-Fock basis, Wherever possible the Lorentz covariance of the proble m is respected, The first three energy-weighted moments of the reduced response are computed, namely, the zeroth moment (Coulomb sum rule), the first moment (related to the position of the quasielastic peak) an d the second moment (related to the peak width or variance). We discus s a procedure to be used in fixing the value of the only free paramete r characterizing the model, namely the Fermi momentum k(F), which is b eing related, rather than to the average nuclear density, to the half- width of the quasielastic response.