Double photoionization of neon with correlated initial states

F. D. COLAVECCHIA AND G. GASANEO

Konigstein

Simposio; International Symposium on (e,2e), Double Photoionization and Related Topics; 2007

Two electron states of simple atoms have been probed by double photoionization (DPI) experiment for many years[1]. Although DPI of Helium atoms has received most of the attention, experimental and theoretical works for heavier species have been performed only recently[2]. However, in these systems the role of the intra and shell correlations is poorly understood. In this work we present theoretical calculations of triple differentialcross sections (TDCS) of DPI of neon atoms, within the theoretical framework of a full numerical C3-model.The electron-nucleus interaction is modeled with a local, radial effective potential that includes exchange[3]. Thecorresponding wave functions for both the initial and final states are obtained by solving the radial Schrödingerequation for each electron. These functions accurately account for the radial correlation. The electron-electronangular correlation is also included in the initial state and the full electronic state has the correct state energy[4].In the final state, the electron-electron correlation is considered a pure Coulomb distortion. We also asume thedipolar approximation for the transition matrix. Computation of the TDCS is performed numerically, by sixdimensionalintegration of the transition matrices elements in length, velocity and acceleration forms. We presentresults for the double photoionization of the inner shell 2s states of Ne, with and without initial state correlationin equal energy sharing collision. We discuss the discrepancies of gauges in this process, in connection withthe introduction of this correlation in the initial state, and compare these results with other proposals of initialstates[5, 6].[1] L Avaldi and A Huetz, J. Phys. B: At. Mol. Opt. Phys. 38 S861 (2005).[2] P Bolognesi et al, J. Phys. B: At. Mol. Opt. Phys. 39 1899 (2006).[3] J D Talman and W F Shadwick, Phys. Rev. A 14 361 (1976).[4] K. V. Rodríguez and G. Gasaneo, J. Phys. B: At. Mol. Opt. Phys. 38 L259 (2005).[5] S H Patil, Eur. J. Phys. 25 91 (2004).[6] P Pluvinage, Ann. Phys. (Paris) 5 145 (1950), J. Phys. Radium 12 789 (1951).