The 11S to 23S and 11S to 23P excitation of helium by electron impact

The R-matrix method calculations of Berrington et al. (1975) and Fon et al. (1978) are extended to the calculation of the integrated and differential cross sections for electron excitation of the ground-state helium atom to the 2 3 S and 2 3 P states in the energy ranges (21.4<or=E<or=30 eV) and (80<or=E<or=200 eV). For intermediate energies (30