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Bulletin of the American Physical Society

The effect of energy and angular momentum gaps in cold and ultracold collisions of H$_2$ molecules

Samantha Fonseca dos Santos, N. Balakrishnan, S. Lepp, Goulven Quéméner, Robert C. Forrey, Phillip C. Stancil

Published Jun 15, 2011• 0 citations
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We calculate the interaction potential between N atoms and NH molecules and use it to investigate cold and ultracold collisions important for sympathetic cooling. The ratio of elastic to inelastic cross sections is large over a wide range of collision energy and magnetic field for most isotopic combinations, so that sympathetic cooling of NH molecules by N atoms is a good prospect. However, there are important effects due to a p-wave shape resonance that may inhibit cooling in some cases. We show that scaling the reduced mass used in the collision is approximately equivalent to scaling the interaction potential. We then explore the dependence of the scattering properties on the reduced mass and explain the resonant effects observed using angular-momentum-insensitive quantum defect theory.
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