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Updated: May 29, 2026

Angle-resolved Photoemission Spectroscopy At Ultra-low Temperatures
Published on: October 9, 2012
Photoassociation spectroscopy of cold he(2 ^{3}s) atoms
N Herschbach1, P J Tol, W Vassen
1Department of Physics and Astronomy, Vrije Universiteit, De Boelelaan 1081, 1081 HV Amsterdam, The Netherlands.
Abstract:
We observe vibrational states by photoassociation spectroscopy of cold He(2 ^{3}S) atoms. Photoassociation resonances are detected as peaks in the Penning ionization rate over a frequency range of 20 GHz below the atomic 2 ^{3}S_{1}-2 ^{3}P_{2} transition frequency. We have observed three vibrational series, of which two can be identified. A possible mechanism to explain the observed increase of the Penning ionization rate is discussed.
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