R-MATRIX WITH PSEUDO-STATES CALCULATION FOR ELECTRON COLLISIONS WITH NEUTRAL BERYLLIUM

We have extended and further improved our previous R-matrix with pseud o-states (RMPS) calculation for electron collisions with beryllium (19 96 J. Phys. B: At. Mel. Opt. Phys. L769-72). Results for transitions f rom the (2s(2))S-1 ground state to the lowest 11 target states with pr incipal quantum number n = 2, 3 are presented for incident energies fr om threshold to 100 eV. In the crucial 'intermediate energy range' of 10-100 eV, our results are in good agreement with those obtained in th e convergent close-coupling (CCC) calculation of Fursa and Bray, where as significant discrepancies are found with predictions from simpler m odels. Consequently, a combination of RMPS and CCC predictions in this region, supplemented by our RMPS results in the low-energy resonance regime and further CCC results above 100 eV incident energy are believ ed to represent the most accurate currently available data for this co llision problem.