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arXiv · 1411.1131

Internal structure and positron annihilation in the four-body MuPs system

Alexei M. Frolov
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Abstract

A large number of bound state properties of the four-body muonium-positronium system MuPs (or $μ^{+} e^{-}_2 e^{+}$) are determined to high accuracy. Based on these expectation values we predict that the weakly-bound four-body MuPs system has the `two-body' cluster structure Mu + Ps. The two neutral clusters Mu ($μ^{+} e^{-}$) and Ps ($e^{+} e^{-}$) interact with each other by the attractive van der Waals forces. By using our expectation values of the electron-positron delta-functions we evaluated the half-life $τ_a$ of the MuPs system against annihilation of the electron-positron pair: $τ_a = \frac{1}Γ \approx 4.071509 \cdot 10^{-10}$ $sec$. The hyperfine structure splitting of the ground state in the MuPs system evaluated with our expectation values is $Δ\approx$ 23.064(5) $MHz$.

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Alexei M. Frolov. 2015-01-07. Internal structure and positron annihilation in the four-body MuPs system. https://doi.org/10.1140/epjd%2Fe2015-50824-2

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