BENCHMARK CALCULATIONS FOR E-H SCATTERING BETWEEN THE N=2 AND N=3 THRESHOLDS

We present eigenphase sums and partial cross sections for elastic scat tering and electron-impact excitation of the n = 2 states of atomic hy drogen for incident electron energies between the n = 2 and n = 3 thre sholds. These results were obtained by using the convergent close-coup ling (CCC), R-matrix with pseudo-states (RMPS), and intermediate-energ y R-matrix (IERM) methods. The agreement between the predictions from all three approaches is excellent, indicating that the effects of both the discrete and the continuum states in the close-coupling expansion have been treated to convergence. Very good agreement is also obtaine d with the experimental data of Williams.