Four-body model for transfer ionization in fast ion-atom collisions

Journal Article · Wed Jan 01 04:00:00 EST 1997 · Physical Review A

DOI:https://doi.org/10.1103/PhysRevA.55.378· OSTI ID:459838

Belkic, D; Mancev, I; Mergel, V ^[1]

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1. University of Stockholm, Atomic Physics, Frescativaegen 24, S-104 05 Stockholm (Sweden)

Total cross sections for transfer ionization in fast collisions of a bare nucleus with helium are examined in the four-body distorted-wave formalism. A special emphasis is given to a proper inclusion of dynamic electron-electron correlation effects. For this purpose, the four-body continuum distorted-wave (CDW-4B) approximation with the correct boundary conditions is introduced. Along with the appropriate potential operators containing a single electron placed on one and/or both nuclear centers, accompanied by the corresponding Coulomb waves for continuum intermediate states, the dielectronic interaction V{sub 12}=1/r{sub 12}{equivalent_to}1/{vert_bar}{rvec r}{sub 1}{minus}{rvec r}{sub 2}{vert_bar} also explicitly appears in the perturbation potential of the transition probability amplitude. The inclusion of the potential V{sub 12} is essential for the description of the Thomas P-e-e scattering, through which one of the target electrons could be captured or ionized without ever experiencing any direct interaction with the projectile P. The total cross sections {sigma}{sub if} due to such a correlated CDW-4B theory are computed exactly and very efficiently by means of precise evaluation of certain seven-dimensional quadratures in momentum space. The proposed method is shown to be superior to the corresponding independent event model (CDW-IEM), which also proceeds through the same effort on multidimensional scattering integrals, but largely overestimates the measured values for {sigma}{sub if}. Comparisons between the present results {sigma}{sub if} and the available experimental data at E=30{endash}600 keV/amu for transfer ionization in the He{sup 2+}-He collision yield satisfactory agreement at impact energies E{ge}80 keV/amu. This is in full harmony with the well-known low-energy limit of the validity of the CDW-3B method assessed previously. {copyright} {ital 1997} {ital The American Physical Society}

• OSTI ID: 459838
• Journal Information: Physical Review A, Journal Name: Physical Review A Journal Issue: 1 Vol. 55; ISSN 1050-2947; ISSN PLRAAN
• Country of Publication: United States
• Language: English

Related Subjects

66 PHYSICS
ATOMIC IONS
CROSS SECTIONS
DISTORTED WAVE THEORY
HELIUM
ION-ATOM COLLISIONS
IONIZATION
MULTICHARGED IONS
PERTURBATION THEORY
SCATTERING