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arXiv · 2005.09102

Interaction potentials and ultracold scattering cross sections for the $^7$Li$^+$-$^7$Li ion-atom system

Abstract

We calculate the isotope independent Li$^+$-Li potential energy curves for the electronic ground and first excited states. Scattering phase shifts and total scattering cross section for the $^7$Li$^+$-$^7$Li collision are calculated with emphasis on the ultra-low energy domain down to the $s$-wave regime. The effect of physically motivated alterations on the calculated potential energy curves is used to determine the bound of accuracy of the low-energy scattering parameters for the ion-atom system. It is found that the scattering length for the A$^2\Sigma_u^+$ state, $a_u$ = 1325 a$_0$, is positive and has well-constrained bounds. For the X$^2\Sigma_g^+$ state, the scattering length, $a_g$ = 20465 a$_0$ has a large magnitude as it is sensitive to the restrained change of the potential, due to the presence of a vibrational state in the vicinity of the dissociation limit.

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A. Pandey, M. Niranjan, N. Joshi, S. A. Rangwala, R. Vexiau, O. Dulieu. 2020-05-18. Interaction potentials and ultracold scattering cross sections for the $^7$Li$^+$-$^7$Li ion-atom system. https://doi.org/10.1103/physreva.101.052702

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