We report on an experimental and theoretical systematic study of double ionization of helium by ion impact in terms of four-particle Dalitz plots. Several collision systems covering abroad range of perturbation parameters η (projectile charge to speed ratio) were investigated. With increasing η we observe a systematic trend from features, characteristic to correlated double-ionization mechanisms, to signatures of higher-order processes not requiring electron-electron correlations [the mechanism called "two-step-two projectile-electron interaction" (TS-2)]. The data for the largest η can qualitatively be amazingly well described by a simple model only including the TS-2 mechanism.
D. Fischer and M. Schulz and K. R. Schneider and M. F. Ciappina and T. Kirchner and A. H. Kelkar and S. Hagman and M. Grieser and K. U. Kuhnel and R. Moshammer and J. H. Ullrich, "Systematic Analysis of Double-Ionization Dynamics Based on Four-Body Dalitz Plots," Physical Review A - Atomic, Molecular, and Optical Physics, vol. 80, no. 6, pp. 062703-1-062703-8, American Physical Society (APS), Dec 2009.
The definitive version is available at https://doi.org/10.1103/PhysRevA.80.062703
Keywords and Phrases
Collision Systems; Double Ionization; Double-ionization Dynamics; Electron Interaction; Electron-electron Correlation; Higher-order Process; Ion Impact; Ionization Mechanisms; Perturbation Parameters; Projectile Charge; Simple Model; Speed Ratio; Systematic Analysis; Systematic Study; Helium; Ion Bombardment; Particle Detectors
International Standard Serial Number (ISSN)
Article - Journal
© 2009 American Physical Society (APS), All rights reserved.
01 Dec 2009