EFFECTIVE COLLISION STRENGTHS FOR 1S-2S AND 1S-2P ELECTRON HYDROGEN-ATOM SCATTERING

Extensive electron-hydrogen atom scattering calculations have recently been performed (Scott et al) using a hybrid model which employs intermediate energy R-matrix theory, pseudostate close-coupling and the second Born approximation. The resulting 1s-2s and 1s-2p cross-sections have been integrated over a Maxwellian electron energy distribution to yield effective collision strengths and rate coefficients for excitation to the n = 2 levels of the hydrogen atom. These parameters are reported for plasma temperatures ranging from 5 × 103 to 5 × 105 K and are fitted to simple analytic formulae. © Royal Astronomical Society.