BEYOND THE TIME-INDEPENDENT MEAN-FIELD THEORY FOR NUCLEAR AND ATOMIC REACTIONS - INCLUSION OF PARTICLE-HOLE CORRELATIONS IN A GENERALIZED RANDOM-PHASE-APPROXIMATION

The time independent mean field method for scattering defines biorthon ormal sets of single-particle wave functions and corresponding creatio n and annihilation operators. Two-particle-two-hole (2p-2h) correlatio ns can be introduced through a generalized random phase approximation; 1p-1h contributions vanish (Brillouin theorem). While the general var iational method for scattering by Giraud and Nagarajan solves inhomoge neous Euler equations by inversion of the standard, Hermitean Hamilton ian, the present approach diagonalizes a non-Hermitean Hamiltonian, wh ich carries the information about entrance and exit channels.