Single and Double Ionization of Helium by the Impact of Fast Charged Particles

Abstract

A survey of the recent literature shows that paradoxes abound in electron- and ion-impact ionization of helium. For example, Schulz et al. [M. Schulz, R. Moshammer, D. Fischer, H. Kollmus, D.H. Madison, S. Jones, J. Ullrich, Nature 422 (2003) 48] found that first-Born and three-body distorted-wave (3DW) theories reproduced their data for single ionization of helium by very fast fully stripped carbon ions in the scattering plane, but not outside the scattering plane. For much slower impacting carbon ions, however, Madison et al. [D.H. Madison, D. Fischer, M. Foster, M. Schulz, R. Moshammer, S. Jones, J. Ullrich, Phys. Rev. Lett. 91 (2003) 253201] found good agreement between 3DW theory and experiment, even outside the scattering plane. This creates a dilemma, since distorted-wave perturbation theories are generally thought to improve with increasing, not decreasing, projectile speed! in this contribution, we will address these and other issues, and suggest possible ways of proceeding.

Department(s)

Physics

Sponsor(s)

National Science Foundation (U.S.)

Keywords and Phrases

3DW; CDW; Cross-Section; Distorted Wave; Electron Impact; Ion Impact; Perturbation Theory; Collisions (Nuclear Physics); Ionization

International Standard Serial Number (ISSN)

0168-583X

Document Type

Article - Journal

Document Version

Citation

File Type

text

Language(s)

English

Rights

© 2005 Elsevier, All rights reserved.

Publication Date

01 Dec 2005

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