Numéro
J. Phys. IV France
Volume 03, Numéro C6, Novembre 1993
International Symposium on (e,2e) Collisions, Double Photoionization and Related Processes
(e,2e) '93
Page(s) C6-21 - C6-28
DOI http://dx.doi.org/10.1051/jp4:1993602
International Symposium on (e,2e) Collisions, Double Photoionization and Related Processes
(e,2e) '93

J. Phys. IV France 03 (1993) C6-21-C6-28

DOI: 10.1051/jp4:1993602

Triply differential (e,2e) cross sections for He from threshold to 50 eV above

C. PAN and A.F. STARACE

Department of Physics and Astronomy, The University of Nebraska, Lincoln, NE 68588-0111, U.S.A.


Abstract
Distorted wave calculations of the triply differential cross sections for electron-impact ionization of He are presented for electrons sharing [MATH] 50 eV excess energy (Ex) and having the coplanar, [MATH] geometry. The results are in good agreement with absolute experimental measurements of T. Rösel et al. [Phys. Rev. A 46 (1992) 2539-2552] and of A. J. Murray, M. B. Woolf, and F. H. Read [J. Phys. B 25 (1992) 3021-3036]. For final state electrons sharing 2 eV excess energy equally, many-body perturbation theory corrections to the authors' first order (e,2e) triply differential cross sections [Phys. Rev. A 45 (1992) 4588-4603] are also presented. These results indicate that singlet-triplet interchannel coupling effects in the final state are very significant ; that initial state correlations are significant near the perpendicular plane, i.e., [MATH] ; and that the polarization effects we include are insignificant. Finally, comparison of our first order results with the semiclassical quanta1 theory results of D. S. F. Crothers [J. Phys. B 19 (1986) 463-483] shows excellent agreement for excess energies [MATH] and for [MATH] ; for [MATH], the two results diverge as [MATH], indicating that experimental tests of the Wannier-Peterkop-Rau theory of three-body Coulomb breakup should be carried out in this energy region.



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