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arXiv · 1903.02243

Ab initio QED treatment of the two-photon annihilation of positrons with bound electrons

V. A. Zaytsev·A. V. Volotka·D. Yu·S. Fritzsche·X. Ma·H. Hu·V. M. Shabaev
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Abstract

The process of a positron $\unicode{x2013}$ bound-electron annihilation with simultaneous emission of two photons is investigated theoretically. A fully relativistic formalism based on $\textit{ab initio}$ QED description of the process is worked out. The developed approach is applied to evaluate the annihilation of a positron with $K$-shell electrons of a silver atom, for which a strong contradiction between theory and experiment was previously stated. The results obtained here resolve this long-standing disagreement and, moreover, demonstrate a sizeable difference with approaches so far used for calculations of the positron $\unicode{x2013}$ bound-electron annihilation process, namely, the $\textit{Lee's}$ and $\textit{impulse}$ approximations.

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V. A. Zaytsev, A. V. Volotka, D. Yu, S. Fritzsche, X. Ma, H. Hu, V. M. Shabaev. 2019-03-06. Ab initio QED treatment of the two-photon annihilation of positrons with bound electrons. https://doi.org/10.1103/physrevlett.123.093401

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