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 energies
- 14 November 1987
- journal article
- Published by IOP Publishing in Journal of Physics B: Atomic and Molecular Physics
- Vol. 20 (21) , L685-L690
- https://doi.org/10.1088/0022-3700/20/21/004
Abstract
The R-matrix method has been employed to study the electron excitation of atomic helium. Nineteen target states (n=1, 2, 3 and 4) have been included in the expansion of the total wavefunction. The results of this calculation are used to obtain the electron-photon coincidence parameters lambda and chi for the excitation 11S-21P at 22, 24, 26.5 and 29.6 eV. The calculated parameters lambda and chi are compared with values obtained from experiments and with earlier 5- and 11-state R-matrix calculations.Keywords
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