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arXiv · 1006.2664

Interatomic Coulombic Decay following Photoionization of the Helium Dimer: Observation of Vibrational Structure

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·J. H. Morilla·W. Schöllkopf·H. Schmidt-Böcking·R. E. Grisenti·R. Dörner
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Abstract

Using synchrotron radiation we simultaneously ionize and excite one helium atom of a helium dimer (He_2) in a shakeup process. The populated states of the dimer ion (i.e. He^[*+](n = 2; 3)-He) are found to deexcite via interatomic coulombic decay. This leads to the emission of a second electron from the neutral site and a subsequent coulomb explosion. In this letter we present a measurement of the momenta of fragments that are created during this reaction. The electron energy distribution and the kinetic energy release of the two He^+ ions show pronounced oscillations which we attribute to the structure of the vibrational wave function of the dimer ion.

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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, J. H. Morilla, W. Schöllkopf, H. Schmidt-Böcking, R. E. Grisenti, R. Dörner. 2010-06-14. Interatomic Coulombic Decay following Photoionization of the Helium Dimer: Observation of Vibrational Structure. https://doi.org/10.1103/physrevlett.104.133401

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