Effects of autoionizing states on two-photon double ionization of the H2 molecule

28th International Conference on Photonic, Electronic and Atomic Collisions

Guan, Xiaoxu^1 ; Bartschat, Klaus^1 ; Schneider, Barry I.^2 ; Koesterke, Lars^3

Department of Physics and Astronomy, Drake University, Des Moines

50322, United States^1

Division of Advanced Cyberinfrastructure, National Science Foundation, Arlington

VA

22230, United States^2

Texas Advanced Computer Center, University of Texas at Austin, Austin

TX

78758, United States^3

关键词: Autoionizing state;    Computational challenges;    Doubly excited state;    Fixed-nuclei approximation;    Generalized cross section;    Intermediate state;    Sequential ionization;    Two-photon double ionization;   

Others  :  https://iopscience.iop.org/article/10.1088/1742-6596/488/1/012024/pdf
DOI  :  10.1088/1742-6596/488/1/012024

来源: IOP

【 摘 要 】

Treating the effects of autoionizing intermediate states on two-photon double ionization (DI) of the H2molecule using time-dependent laser pulses is a significant computational challenge. Relatively long exposure times are critical to understanding the dynamics. Using the fixed-nuclei approximation, we demonstrate how the doubly excited states enhance the angle-integrated generalized cross sections in H2, and how they affect the angular distribution pattern of the ejected electrons. As the energy approaches the threshold for sequential DI, there is a sharp rise in the cross section due to virtual sequential ionization.