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arXiv · 1001.2741

The ^1S+^1S asymptote of Sr_2 studied by Fourier-transform spectroscopy

A. Stein·H. Knöckel·E. Tiemann
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Abstract

An experimental study of the long range behavior of the ground state X^1Σ^+_g of Sr_2 is performed by high resolution spectroscopy of asymptotic vibrational levels and the use of available photoassociation data. Ground state levels as high as v"=60 (outer turning point at 23 Åand 0.1 cm^-1 below the asymptote) could be observed by Fourier-transform spectroscopy of fluorescence progressions induced by single frequency laser excitation of the v'=4, J'=9 rovibrational level of the state 2^1Σ^+_u. A precise value of the scattering length for the isotopologue ^88Sr_2 is derived and transferred to all other isotopic combinations by mass scaling with the given potential. The derived potential together with already published information about the state 2^1Σ^+_u directs to promising optical paths for producing cold molecules in the electronic ground state from an ultracold ensemble of Sr atoms.

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A. Stein, H. Knöckel, E. Tiemann. 2010-04-16. The ^1S+^1S asymptote of Sr_2 studied by Fourier-transform spectroscopy. https://doi.org/10.1140/epjd%2Fe2010-00058-y

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