Published In

Physical Review A

Document Type

Article

Publication Date

11-1-1992

Abstract

A technique for evaluating cross sections for two-electron excitation in collisions of atoms with fast particles of charge ZP is presented. The atomic wave function is approximated by a sum of pair products of one-electron wave functions, with the coefficients chosen by diagonalizing the fully correlated twoelectron Hamiltonian. Thus spatial correlation is included in both the asymptotic and scattering regions by using these configuration-interaction (Cl) wave functions for initial, intermediate, and final states. Use of CI wave function also allows the first-order contributions to be expressed in closed, analytical form. Both the energy-conserving and energy-nonconserving parts of the second-order amplitude are evaluated. The former (a correlated generalization of the independent-electron approximation) is analytical and the latter is a one-dimensional integral. In helium it is found that the double-excitation cross sections are sensitive to the sign of the projectile charge, but that the energy region where this sensitivity is of the same order as for double ionization is 0.1 to 0.5 Me V /amu, whereas the latter has peak charge sensitivity at 1.5 MeV /amu. Comparison is made with some experimental results.

Description

At the time of publication, Jack Straton was affiliated with California State University.

This is the publisher version archived with permission.

https://doi.org/10.1103/PhysRevA.46.5514

Copyright 1992 American Physical Society.

DOI

10.1103/PhysRevA.46.5514

Persistent Identifier

https://archives.pdx.edu/ds/psu/25890

Included in

Physics Commons

Share

COinS