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arXiv · 1302.2397

Cusp Kernels for Velocity-Changing Collisions

B. H. McGuyer·R. Marsland III·B. A. Olsen·W. Happer
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Abstract

We introduce an analytical kernel, the "cusp" kernel, to model the effects of velocity-changing collisions on optically pumped atoms in low-pressure buffer gases. Like the widely used Keilson-Storer kernel [J. Keilson and J. E. Storer, Q. Appl. Math. 10, 243 (1952)], cusp kernels are characterized by a single parameter and preserve a Maxwellian velocity distribution. Cusp kernels and their superpositions are more useful than Keilson-Storer kernels, because they are more similar to real kernels inferred from measurements or theory and are easier to invert to find steady-state velocity distributions.

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B. H. McGuyer, R. Marsland III, B. A. Olsen, W. Happer. 2013-02-11. Cusp Kernels for Velocity-Changing Collisions. https://doi.org/10.1103/physrevlett.108.183202

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