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arXiv · physics/9703011

Photodetachment study of the 1s3s4s ^4S resonance in He^-

Abstract

A Feshbach resonance associated with the 1s3s4s ^{4}S state of He^{-} has been observed in the He(1s2s ^{3}S) + e^- (εs) partial photodetachment cross section. The residual He(1s2s ^{3}S) atoms were resonantly ionized and the resulting He^+ ions were detected in the presence of a small background. A collinear laser-ion beam apparatus was used to attain both high resolution and sensitivity. We measured a resonance energy E_r = 2.959 255(7) eV and a width Γ= 0.19(3) meV, in agreement with a recent calculation.

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Andreas E. Klinkmueller, Gunnar Haeffler, Dag Hanstorp, Igor Yu. Kiyan, Uldis Berzinsh, Christopher W. Ingram, David J. Pegg, James R. Peterson. 1997-06-06. Photodetachment study of the 1s3s4s ^4S resonance in He^-. https://doi.org/10.1103/physreva.56.2788

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