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arXiv · 0901.1281

Quasi-Universal Dipolar Scattering in Cold and Ultracold Gases

J. L. Bohn·M. Cavagnero·C. Ticknor
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Abstract

We investigate the scattering cross section of aligned dipolar molecules in low-temperature gases. Over a wide range of collision energies relevant to contemporary experiments, the cross section declines in inverse proportion to the collision speed, and is given nearly exactly by a simple semiclassical formula. At yet lower energies, the cross section becomes independent of energy, and is reproduced within the Born approximation to within corrections due to the s-wave scattering length. While these behaviors are universal for all polar molecules, nevertheless interesting deviations from universality are expected to occur in the intermediate energy range.

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J. L. Bohn, M. Cavagnero, C. Ticknor. 2009-01-09. Quasi-Universal Dipolar Scattering in Cold and Ultracold Gases. https://doi.org/10.1088/1367-2630%2F11%2F5%2F055039

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