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arXiv · 1006.2667

Single photon double ionization of the helium dimer

T. Havermeier·T. Jahnke·K. Kreidi·R. Wallauer·S. Voss·M. Schöffler·S. Schössler·L. Foucar·N. Neumann·J. Titze·H. Sann·M. Kühnel·J. Voigtsberger·A. Malakzadeh·N. Sisourat·W. Schöllkopf·H. Schmidt-Böcking·R. E. Grisenti·R. Dörner
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Abstract

We show that a single photon can ionize the two helium atoms of the helium dimer in a distance up to 10 {\deg}A. The energy sharing among the electrons, the angular distributions of the ions and electrons as well as comparison with electron impact data for helium atoms suggest a knock-off type double ionization process. The Coulomb explosion imaging of He_2 provides a direct view of the nuclear wave function of this by far most extended and most diffuse of all naturally existing molecules.

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T. Havermeier, T. Jahnke, K. Kreidi, R. Wallauer, S. Voss, M. Schöffler, S. Schössler, L. Foucar, N. Neumann, J. Titze, H. Sann, M. Kühnel, J. Voigtsberger, A. Malakzadeh, N. Sisourat, W. Schöllkopf, H. Schmidt-Böcking, R. E. Grisenti, R. Dörner. 2010-06-14. Single photon double ionization of the helium dimer. https://doi.org/10.1103/physrevlett.104.153401

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