Resonances in H-associated with the n=2, 3 and 4 hydrogenic thresholds

Abstract
The energies and widths of resonances in the scattering of electrons by hydrogen atoms are calculated for incident electron energies from 0.686 to 0.9374 Ryd using a fifteen-state R-matrix calculation. The results are compared with available experimental data and theoretical calculations. The arrangement of these resonances in series converging to the n=2, 3 and 4 thresholds is also studied.