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arXiv · 1806.05214

Direct observation of interatomic Coulombic decay and subsequent ion-atom scattering in helium nanodroplets

F. Wiegandt·F. Trinter·K. Henrichs·D. Metz·M. Pitzer·M. Waitz·E. Jabbour al Maalouf·C. Janke·J. Rist·N. Wechselberger·T. Miteva·S. Kazandjian·M. Schöffler·N. Sisourat·T. Jahnke·R. Dörner
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Abstract

We report on the experimental observation of interatomic Coulombic decay (ICD) in pure $^4$He nanoclusters of mean sizes between $N \approx$ 5000 and 30000 and the subsequent scattering of energetic He$^+$ fragments inside the neutral cluster by using cold target recoil ion momentum spectroscopy. ICD is induced in He clusters by using vacuum ultraviolet light of $h\nu =$ 67 eV from the BESSY II synchrotron. The electronic decay creates two neighboring ions in the cluster at a well-defined distance. The measured fragment energies and angular correlations show that a main energy loss mechanism of these ions inside the cluster is a single hard binary collision with one atom of the cluster.

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F. Wiegandt, F. Trinter, K. Henrichs, D. Metz, M. Pitzer, M. Waitz, E. Jabbour al Maalouf, C. Janke, J. Rist, N. Wechselberger, T. Miteva, S. Kazandjian, M. Schöffler, N. Sisourat, T. Jahnke, R. Dörner. 2018-06-13. Direct observation of interatomic Coulombic decay and subsequent ion-atom scattering in helium nanodroplets. https://doi.org/10.1103/physreva.100.022707

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