Absolute total cross sections for electron-impact double ionization of He(1s2s3S) and He−(1s2s2p4P)

Génévriez, Matthieu;Defrance, Pierre;Jureta, Jozo;Urbain, Xavier
(2018) The European Physical Journal D — Vol. 73, n° 2, p. 73-30 (2019)

Files

Génévriez2019_Article_AbSoluteTotalCroSSSectionSForE.pdf
  • Open Access
  • Adobe PDF
  • 433.38 KB

Details

Authors
Abstract
We report on the experimental determination of absolute, total cross sections for electron-impact double ionization of helium in its metastable 1s2s 3S state and of the helium negative ion He􀀀(1s2s2p 4P). Cross sections are measured for impact energies ranging from threshold to 1000 eV using the animated crossed beams technique. The fast, pure beam of metastable helium required for the experiment is produced by photodetachment of fast He􀀀 ions. Results for He(1s2s 3S) are compared to those for He(1s2 1S), and exhibit similar magnitude and behaviour. The cross section for He􀀀 is large compared to other negative ions and indicates the predominance of indirect ionization channels at large impact energies.
Affiliations

Citations

Génévriez, M., Defrance, P., Jureta, J., & Urbain, X. (2018). Absolute total cross sections for electron-impact double ionization of He(1s2s3S) and He−(1s2s2p4P). The European Physical Journal D, 73(2), 73-30. https://doi.org/10.1140/epjd/e2018-90566-y (Original work published 2019)