Nondipole Effects in Double Photoionization of He

Journal Article · Mon Jan 09 04:00:00 EST 2006 · AIP Conference Proceedings

DOI:https://doi.org/10.1063/1.2165614· OSTI ID:20797872

Istomin, A Y; Starace, A F ^[1]; Manakov, N L; Meremianin, A V ^[2]

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1. Department of Physics and Astronomy, University of Nebraska, Lincoln, NE 68588-0111 (United States)
2. Physics Department, Voronezh State University, Voronezh 394006 (Russian Federation)

Lowest-order nondipole effects are studied in double photoionization (DPI) of the He atom. Ab initio parametrizations of the quadrupole transition amplitude for DPI from the 1S0-state are presented in terms of the exact two-electron reduced matrix elements. Parametrizations for the dipole-quadrupole triply differential cross section (TDCS) and doubly differential cross section (DDCS) are presented in terms of polarization-independent amplitudes for the case of an elliptically polarized photon. Expressions for the DDCS in terms of the reduced two-electron matrix elements are also given. A general analysis of retardation-induced asymmetries of the TDCS including the circular dichroism effect at equal energy sharing is presented. Our numerical results exhibit a nondipole forward-backward asymmetry in the TDCS for DPI of He at an excess energy of 450 eV that is in qualitative agreement with existing experimental data.

• OSTI ID: 20797872
• Journal Information: AIP Conference Proceedings, Journal Name: AIP Conference Proceedings Journal Issue: 1 Vol. 811; ISSN APCPCS; ISSN 0094-243X
• Country of Publication: United States
• Language: English

Related Subjects

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