Perturbative calculation of the cross section in double ionization by high-energy Compton scattering
Department of Physics, Faculty of Arts and Sciences, University of Rijeka, 180 Rijeka, Croatia
2 Rudjer Bošković Institute, P.O. Box 180, 625 Zagreb, Croatia
Revised: 1 February 2007
Published online: 7 March 2007
In this paper we investigate double ionization in high-energy Compton scattering from the He-atom including both the shake-off mechanism and a perturbative correction to that mechanism. The correction is calculated in second-order perturbation theory and includes Coulomb electron-electron interaction in addition to the correlation in the ground state of the He-atom. Our calculations for the ratio of double to single cross section cover the range from 30 to 300 keV of impact photon energy and explain the slow convergence of the ratio towards the asymptotic value.
PACS: 32.80.Fb – Photoionization of atoms and ions / 32.80.Cy – Atomic scattering, cross sections, and form factors; Compton scattering
© EDP Sciences, Società Italiana di Fisica, Springer-Verlag, 2007