### Abstract

The process of a positron-bound-electron annihilation with simultaneous emission of two photons is investigated theoretically. A fully relativistic formalism based on an 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 longstanding disagreement and, moreover, demonstrate a sizable difference with approaches so far used for calculations of the positron-bound-electron annihilation process, namely, Lee's and the impulse approximations.

Original language | English |
---|---|

Article number | 093401 |

Journal | Physical Review Letters |

Volume | 123 |

Issue number | 9 |

DOIs | |

Publication status | Published - 26 Aug 2019 |

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### Scopus subject areas

- Physics and Astronomy(all)

### Cite this

*Physical Review Letters*,

*123*(9), [093401]. https://doi.org/10.1103/PhysRevLett.123.093401

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*Physical Review Letters*, vol. 123, no. 9, 093401. https://doi.org/10.1103/PhysRevLett.123.093401

**Ab initio QED Treatment of the Two-Photon Annihilation of Positrons with Bound Electrons.** / Zaytsev, V. A.; Volotka, A. V.; Yu, D.; Fritzsche, S.; Ma, X.; Hu, H.; Shabaev, V. M.

Research output › › peer-review

TY - JOUR

T1 - Ab initio QED Treatment of the Two-Photon Annihilation of Positrons with Bound Electrons

AU - Zaytsev, V. A.

AU - Volotka, A. V.

AU - Yu, D.

AU - Fritzsche, S.

AU - Ma, X.

AU - Hu, H.

AU - Shabaev, V. M.

PY - 2019/8/26

Y1 - 2019/8/26

N2 - The process of a positron-bound-electron annihilation with simultaneous emission of two photons is investigated theoretically. A fully relativistic formalism based on an 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 longstanding disagreement and, moreover, demonstrate a sizable difference with approaches so far used for calculations of the positron-bound-electron annihilation process, namely, Lee's and the impulse approximations.

AB - The process of a positron-bound-electron annihilation with simultaneous emission of two photons is investigated theoretically. A fully relativistic formalism based on an 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 longstanding disagreement and, moreover, demonstrate a sizable difference with approaches so far used for calculations of the positron-bound-electron annihilation process, namely, Lee's and the impulse approximations.

UR - http://www.scopus.com/inward/record.url?scp=85072017452&partnerID=8YFLogxK

U2 - 10.1103/PhysRevLett.123.093401

DO - 10.1103/PhysRevLett.123.093401

M3 - Article

VL - 123

JO - Physical Review Letters

JF - Physical Review Letters

SN - 0031-9007

IS - 9

M1 - 093401

ER -