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arXiv · 1509.07253

Positronium collisions with rare-gas atoms

G. F. Gribakin·A. R. Swann·R. S. Wilde·I. I. Fabrikant
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Abstract

We calculate elastic scattering of positronium (Ps) by the Xe atom using the recently developed pseudopotential method [I. I. Fabrikant and G. F. Gribakin, Phys. Rev. A 90, 052717 (2014)] and review general features of Ps scattering from heavier rare-gas atoms: Ar, Kr, and Xe. The total scattering cross section is dominated by two contributions: elastic scattering and Ps ionization (breakup). To calculate the Ps ionization cross sections we use the binary-encounter method for Ps collisions with an atomic target. Our results for the ionization cross section agree well with previous calculations carried out in the impulse approximation. Our total Ps-Xe cross section, when plotted as a function of the projectile velocity, exhibits similarity with the electron-Xe cross section for the collision velocities higher than 0.8 a.u., and agrees very well with the measurements at Ps velocities above 0.5 a.u.

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G. F. Gribakin, A. R. Swann, R. S. Wilde, I. I. Fabrikant. 2015-09-24. Positronium collisions with rare-gas atoms. https://doi.org/10.1088/0953-4075/49/6/064004

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