Low energy scattering of electrons by helium atoms

The R-matrix method is used to solve equations describing the scattering of electrons by helium atoms for incident energies near the n=2 thresholds. The 1 1 S,2 3 S,2 1 S,2 3 P and 2 1 P target eigenstates which are included in the expansion of the total wavefunction are represented by configuration-interaction wavefunctions. In addition 1 P and 1 D pseudostates are retained in some of the calculations. Elastic and inelastic scattering cross sections are calculated and are compared with experiment and with other theories wherever possible. Particular attention is paid to resonances and cusps which dominate the cross sections in this energy region.