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arXiv · 0706.2290

Study of the Born-Oppenheimer Approximation for Mass-Scaling of Cold Collision Properties

Stephan Falke·Eberhard Tiemann·Christian Lisdat
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Abstract

Asymptotic levels of the A $^1Σ_u^+$ state of the two isotopomers $^{39}{\rm K}_2$ and $^{39}{\rm K}^{41}{\rm K}$ up to the dissociation limit are investigated with a Doppler-free high resolution laser-spectroscopic experiment in a molecular beam. The observed level structure can be reproduced correctly only if a mass dependent correction term is introduced for the interaction potential. The applied relative correction in the depth of the potential is $10^{-6}$, which is in the order of magnitude expected for corrections of the Born-Oppenheimer approximation. A similar change in ground state potentials might lead to significant changes of mass-scaled properties describing cold collisions like the s-wave scattering length.

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Stephan Falke, Eberhard Tiemann, Christian Lisdat. 2007-06-15. Study of the Born-Oppenheimer Approximation for Mass-Scaling of Cold Collision Properties. https://doi.org/10.1103/physreva.76.012724

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