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arXiv · 1208.6440

Threshold photodetachment in a repulsive potential

Anton O. Lindahl·Johan Rohlén·Hannes Hultgren·Igor Yu. Kiyan·David J. Pegg·C. Wesley Walter·Dag Hanstorp
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Abstract

We report on the first experimental observation of a new threshold behavior observed in the 5g partial channel in photodetachment of K-. It arises from the repulsive polarization interaction between the detached electron and the residual K(5g) atom, which has a large negative dipole polarizability. In order to account for the observation in the K(5g) channel, we have developed a semiclassical model that predicts an exponential energy dependence for the cross section. The measurements were made with collinear laser-ion beams and a resonance ionization detection scheme.

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Anton O. Lindahl, Johan Rohlén, Hannes Hultgren, Igor Yu. Kiyan, David J. Pegg, C. Wesley Walter, Dag Hanstorp. 2012-08-31. Threshold photodetachment in a repulsive potential. https://doi.org/10.1103/physrevlett.108.033004

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