Nondipole Effects in Double Photoionization of He
Abstract
Lowestorder nondipole effects are studied in double photoionization (DPI) of the He atom. Ab initio parametrizations of the quadrupole transition amplitude for DPI from the 1S0state are presented in terms of the exact twoelectron reduced matrix elements. Parametrizations for the dipolequadrupole triply differential cross section (TDCS) and doubly differential cross section (DDCS) are presented in terms of polarizationindependent amplitudes for the case of an elliptically polarized photon. Expressions for the DDCS in terms of the reduced twoelectron matrix elements are also given. A general analysis of retardationinduced asymmetries of the TDCS including the circular dichroism effect at equal energy sharing is presented. Our numerical results exhibit a nondipole forwardbackward asymmetry in the TDCS for DPI of He at an excess energy of 450 eV that is in qualitative agreement with existing experimental data.
 Authors:
 Department of Physics and Astronomy, University of Nebraska, Lincoln, NE 685880111 (United States)
 Physics Department, Voronezh State University, Voronezh 394006 (Russian Federation)
 Publication Date:
 OSTI Identifier:
 20797872
 Resource Type:
 Journal Article
 Resource Relation:
 Journal Name: AIP Conference Proceedings; Journal Volume: 811; Journal Issue: 1; Conference: International symposium on (e,2e) double photoionization, and related topics; 13. international symposium on polarization and correlation in electronic and atomic collisions, Buenos Aires (Argentina), 2830 Jul 2005; Other Information: DOI: 10.1063/1.2165614; (c) 2006 American Institute of Physics; Country of input: International Atomic Energy Agency (IAEA)
 Country of Publication:
 United States
 Language:
 English
 Subject:
 74 ATOMIC AND MOLECULAR PHYSICS; ASYMMETRY; DICHROISM; DIFFERENTIAL CROSS SECTIONS; DIPOLES; ELECTRONS; ENERGY LEVELS; EV RANGE; HELIUM; MATRIX ELEMENTS; PHOTOIONIZATION; PHOTONS; POLARIZATION; QUADRUPOLES; TRANSITION AMPLITUDES
Citation Formats
Istomin, A. Y., Starace, A. F., Manakov, N. L., and Meremianin, A. V. Nondipole Effects in Double Photoionization of He. United States: N. p., 2006.
Web. doi:10.1063/1.2165614.
Istomin, A. Y., Starace, A. F., Manakov, N. L., & Meremianin, A. V. Nondipole Effects in Double Photoionization of He. United States. doi:10.1063/1.2165614.
Istomin, A. Y., Starace, A. F., Manakov, N. L., and Meremianin, A. V. Mon .
"Nondipole Effects in Double Photoionization of He". United States.
doi:10.1063/1.2165614.
@article{osti_20797872,
title = {Nondipole Effects in Double Photoionization of He},
author = {Istomin, A. Y. and Starace, A. F. and Manakov, N. L. and Meremianin, A. V.},
abstractNote = {Lowestorder nondipole effects are studied in double photoionization (DPI) of the He atom. Ab initio parametrizations of the quadrupole transition amplitude for DPI from the 1S0state are presented in terms of the exact twoelectron reduced matrix elements. Parametrizations for the dipolequadrupole triply differential cross section (TDCS) and doubly differential cross section (DDCS) are presented in terms of polarizationindependent amplitudes for the case of an elliptically polarized photon. Expressions for the DDCS in terms of the reduced twoelectron matrix elements are also given. A general analysis of retardationinduced asymmetries of the TDCS including the circular dichroism effect at equal energy sharing is presented. Our numerical results exhibit a nondipole forwardbackward asymmetry in the TDCS for DPI of He at an excess energy of 450 eV that is in qualitative agreement with existing experimental data.},
doi = {10.1063/1.2165614},
journal = {AIP Conference Proceedings},
number = 1,
volume = 811,
place = {United States},
year = {Mon Jan 09 00:00:00 EST 2006},
month = {Mon Jan 09 00:00:00 EST 2006}
}

Lowestorder nondipole effects are studied systematically in double photoionization (DPI) of the He atom. Ab initio parametrizations of the quadrupole transition amplitude for DPI from the {sup 1}S{sub 0} state are presented in terms of the exact twoelectron radial matrix elements. Analytic expressions for these matrix elements within lowestorder perturbation theory (LOPT) in the interelectron interaction are also given. The corresponding parametrizations for the dipolequadrupole triply differential cross section (TDCS) are presented for the case of an elliptically polarized photon. A general analysis of retardationinduced asymmetries of the TDCS including the circular dichroism effect at equal energy sharing is presented.more »

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