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arXiv · 0708.0931

Spectroscopy of the a^3Σ_u^+ state and the coupling to the X^1Σ_g^+ state of K_2

A. Pashov·P. Popov·H. Knöckel·E. Tiemann
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Abstract

We report on high resolution Fourier-transform spectroscopy of fluorescence to the a^3Σ_u^+ state excited by two-photon or two-step excitation from the X^1Σ_g^+ state to the 2^3Π_g state in the molecule K_2. These spectroscopic data are combined with recent results of Feshbach resonances and two-color photoassociation spectra for deriving the potential curves of X^1Σ_g^+ and a^3Σ_u^+ up to the asymptote. The precise relative position of the triplet levels with respect of the singlet levels was achieved by including the excitation energies from the X^1Σ_g^+ state to the 2^3Π_g state and down to the a^3Σ_u^+ state in the simultaneous fit of both potentials. The derived precise potential curves allow for reliable modeling of cold collisions of pairs of potassium atoms in their ^2S ground state.

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A. Pashov, P. Popov, H. Knöckel, E. Tiemann. 2007-10-05. Spectroscopy of the a^3Σ_u^+ state and the coupling to the X^1Σ_g^+ state of K_2. https://doi.org/10.1140/epjd%2Fe2007-00307-2

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