A 29-STATE R-MATRIX INVESTIGATION OF RESONANCES IN E(-)-HE SCATTERINGAT LOW ENERGIES .2. 1(1)S-2(3,1)P EXCITATION CROSS-SECTIONS AND THE ELECTRON-PHOTON COINCIDENCE PARAMETERS-LAMBDA AND VERTICAL-BAR-CHI-VERTICAL-BAR

Fon and Lim have reported the 11-state and the 19-state R-matrix calcu lations of 1(1)S-2(3,1)P differential cross sections at low energies. Considerable qualitative agreement had been achieved between the R-mat rix calculations and the experiments. To establish quantitative agreem ent, the 29-state R-matrix calculation of Sawey et al is extended in t his paper to obtain 1(1)S-2(3,1)P excitation cross sections and the el ectron-photon coincidence parameters lambda and \chi\ at 500 energies ranging from the 2(3)P threshold to 24.2eV for scattering angles 20 de grees, 30 degrees, 55 degrees, 60 degrees, 90 degrees, 120 degrees, 12 5 degrees, 140 degrees. The convergence of the R-matrix calculations i n shape and magnitude of the cross sections is reexamined. The calcula tions are compared with the experiments and a new normalization proced ure is proposed to calibrate the experimental cross sections.