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arXiv · 1012.2814

Cold and ultracold NH--NH collisions in magnetic fields

Liesbeth M. C. Janssen·Piotr. S. Żuchowski·Ad van der Avoird·Gerrit C. Groenenboom·Jeremy M. Hutson
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Abstract

Elastic and spin-changing inelastic collision cross sections are presented for cold and ultracold magnetically trapped NH. The cross sections are obtained from coupled-channel scattering calculations as a function of energy and magnetic field. We specifically investigate the influence of the intramolecular spin-spin, spin-rotation, and intermolecular magnetic dipole coupling on the collision dynamics. It is shown that $^{15}$NH is a very suitable candidate for evaporative cooling experiments. The dominant trap-loss mechanism in the ultracold regime originates from the intermolecular dipolar coupling term. At higher energies and fields, intramolecular spin-spin coupling becomes increasingly important. Our qualitative results and conclusions are fairly independent of the exact form of the potential and of the size of the channel basis set.

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Liesbeth M. C. Janssen, Piotr. S. Żuchowski, Ad van der Avoird, Gerrit C. Groenenboom, Jeremy M. Hutson. 2010-12-13. Cold and ultracold NH--NH collisions in magnetic fields. https://doi.org/10.1103/physreva.83.022713

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