Spectrum of two quasiequal-energy electrons ejected by a high-energy photon
Max-Planck-Institut für Quantenoptik,
Hans-Kopfermann-strasse 1, 85748 Garching, Germany
2 Instituto de Astronomía y Física del Espacio, Casilla de Correo 67, Sucursal 28, 1428 Buenos Aires, Argentina
Published online: 15 October 2000
We present numerical results for the photoelectron spectrum in double ionization by keV photons in the quasiequal-energy sharing region. In this region of the spectrum, the relevant ionizing mechanism is due to a mutual sharing of the photon momentum by both electrons, with small momentum transferred to the atomic nucleus. Calculations were performed for photon energies of 25 and 50 keV, where retardation effects are fundamental, while final-state correlations are of minor importance. The spectra present a two-peak structure, with maxima located at the photoelectron energies ε1 = ω /2 ± √( ω3/8c2), with ω the photon energy in atomic units. We discuss the general features of the spectrum in terms of the picture of the photoionization of two free electrons, and we propose a way of detecting the contribution by experiments.
PACS: 32.80.Fb – Photoionization of atoms and ions / 33.60.-q – Photoelectron spectra
© EDP Sciences, Società Italiana di Fisica, Springer-Verlag, 2000