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arXiv · 1709.00394

Many-body theory for positronium-atom interactions

D. G. Green·A. R. Swann·G. F. Gribakin
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Abstract

A many-body-theory approach has been developed to study positronium-atom interactions. As first applications, we calculate the elastic scattering and momentum-transfer cross sections and the pickoff annihilation rate $^1Z_\text{eff}$ for Ps collisions with He and Ne. The cross section for He is in agreement with previous coupled-state calculations, and the momentum-transfer cross section for Ne agrees with available experimental data. $^1Z_\text{eff}$ is found to be 0.13 and 0.26 for He and Ne, respectively, in excellent agreement with the measured values.

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D. G. Green, A. R. Swann, G. F. Gribakin. 2017-09-01. Many-body theory for positronium-atom interactions. https://doi.org/10.1103/physrevlett.120.183402

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