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.

Collision strengths for all transitions among states up to the n=5 level are reported in the energy range below 1.96 Ryd. The R-matrix and no-exchange programs have been used for partial waves with L9 respectively. The results are analysed in detail highlighting the resonance structure. They are also compared with other results. The effective collision strengths obtained after averaging the collision strengths over a Maxwellian distribution of electron velocities are listed at temperatures below 50000 K. Though the results require an improvement especially in the intermediate energy region, nevertheless they are probably the best available for most of the transitions.

Electron collision strengths for all transitions among states up 10 the n = 5 level of Hei are reported in the energy range below 7 Ryd. The R-matrix and no exchange programs have been used for partial waves with angular momentum L a 9 and L > 9 respectively. The resonances in the collision strengths are highlighted and comparisons are made with the available theoretical and experimental data. Effective collision strengths obtained after averaging the collision strengths over a Maxwellian distribution of electron velocities are tabulated for transitions among states u p to the n = 4 level in the electron temperature range below 100 000 K.

The ratio of distances of consecutive resonances in H- converging to the nth threshold are determined for n

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