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arXiv · 0810.0417

Anisotropic fragmentation in low-energy dissociative recombination

S. Novotny·H. Rubinstein·H. Buhr·O. Novotný·J. Hoffmann·M. B. Mendes·D. A. Orlov·M. H. Berg·M. Froese·A. S. Jaroshevich·B. Jordon-Thaden·C. Krantz·M. Lange·M. Lestinsky·A. Petrignani·I. F. Schneider·D. Shafir·F. O. Waffeu Tamo·D. Zajfman·D. Schwalm·A. Wolf
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Abstract

On a dense energy grid reaching up to 75 meV electron collision energy the fragmentation angle and the kinetic energy release of neutral dissociative recombination fragments have been studied in a twin merged beam experiment. The anisotropy described by Legendre polynomials and the extracted rotational state contributions were found to vary on a likewise narrow energy scale as the rotationally averaged rate coefficient. For the first time angular dependences higher than 2$^{nd}$ order could be deduced. Moreover, a slight anisotropy at zero collision energy was observed which is caused by the flattened velocity distribution of the electron beam.

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S. Novotny, H. Rubinstein, H. Buhr, O. Novotný, J. Hoffmann, M. B. Mendes, D. A. Orlov, M. H. Berg, M. Froese, A. S. Jaroshevich, B. Jordon-Thaden, C. Krantz, M. Lange, M. Lestinsky, A. Petrignani, I. F. Schneider, D. Shafir, F. O. Waffeu Tamo, D. Zajfman, D. Schwalm, A. Wolf. 2008-10-02. Anisotropic fragmentation in low-energy dissociative recombination. https://doi.org/10.1088/1742-6596/192/1/012024

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