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Positronium-Atom Collisions

H R J Walters·A C H Yu·S Sahoo·Sharon Gilmore
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Abstract

New results are presented for Ps(1s) scattering by H(1s), He(1$^1$S) and Li(2s). Calculations have been performed in a coupled state framework, usually employing pseudostates, and allowing for excitation of both the Ps and the atom. In the Ps(1s)-H(1s) calculations the H$^-$ formation channel has also been included using a highly accurate H$^-$ wave function. Resonances resulting from unstable states in which the positron orbits H$^-$ have been calculated and analysed. The new Ps(1s)-He(1$^1$S) calculations still fail to resolve existing discrepancies between theory and experiment at very low energies. The possible importance of the Ps$^-$ formation channel in all three collision systems is discussed.

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H R J Walters, A C H Yu, S Sahoo, Sharon Gilmore. 2004-01-25. Positronium-Atom Collisions. https://doi.org/10.1016/j.nimb.2004.03.047

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