Electron impact excitation of the n3,1P (n=2, 3 and 4) states of helium
- 28 April 1991
- journal article
- Published by IOP Publishing in Journal of Physics B: Atomic, Molecular and Optical Physics
- Vol. 24 (8) , 2161-2182
- https://doi.org/10.1088/0953-4075/24/8/026
Abstract
The authors have used the results of 11-state and 19-state R-matrix calculations to obtain differential cross sections and electron-photon coincidence parameters lambda and mod chi mod for the excitations 11S to n3,1P (n=2, 3 and 4) at energies 22, 24, 26.5 and 29.6 eV. Convergence studies on the five-state, 11-state and 19-state R-matrix calculations on lambda , mod chi mod and differential cross sections have been carried out. The calculated Stokes parameters and Lperpendicular to and gamma parameters are compared with experiments, and the n independence of these parameters and the differential cross sections as predicted by Csanak et al. is found to be not particularly strong at low energies.Keywords
This publication has 32 references indexed in Scilit:
- Collisional alignment and orientation of atomic outer shells I. Direct excitation by electron and atom impactPhysics Reports, 1988
- Correlations in Electron-Atom ScatteringPublished by Elsevier ,1988
- Electron excitation in helium: including the n=4 levels in an R-matrix calculationJournal of Physics B: Atomic and Molecular Physics, 1987
- Electron impact excitation of rare gases: differential cross sections and angular correlation parameters for neon, argon, krypton and xenonJournal of Physics B: Atomic and Molecular Physics, 1987
- A 19-state R-matrix calculation of the electron-photon coincidence parameters lambda and chi for the electron excitation of 11S-21P in helium at low energiesJournal of Physics B: Atomic and Molecular Physics, 1987
- R -matrix theory of electron scattering at intermediate energiesProceedings of the Royal Society of London. Series A. Mathematical and Physical Sciences, 1987
- Alignment and orientation in He 21P and 31P excitation by electron impactJournal of Physics B: Atomic and Molecular Physics, 1987
- Electron-photon coincidence parameters for the excitation of the n3P (n=2-8) states of heliumJournal of Physics B: Atomic and Molecular Physics, 1986
- Electron excitation from the 11S, 23S and 21S states of helium. An eleven-state R-matrix calculationJournal of Physics B: Atomic and Molecular Physics, 1985
- Experimental and (first-order many-body) theoretical differential and integral cross sections for excitation of thestates of He by electron impact at 29.2 and 39.7 eVPhysical Review A, 1975