Two-photon decay of para-positronium within a composite approach

Milena Piotrowska; Francesco Giacosa

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arXiv · 2407.20834

Two-photon decay of para-positronium within a composite approach

Milena Piotrowska·Francesco Giacosa

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Abstract

The decay of the para-positronium into two photons is studied in the framework of a composite Quantum Field Theoretical approach. This amounts to the evaluation of the electron-positron dressing together with the Weinberg compositeness condition for the positronium and the triangle-shaped diagram with virtual electrons circulating in it, leading to the two-photon final state. An important role is played by the positronium-electron-positron vertex, which is linked to the wave function of the para-positronium. We show how possible choices for the vertex function affect the $\gamma \gamma$ decay rate. Outlooks to other decay channels and to other positronia are presented.

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Milena Piotrowska, Francesco Giacosa. 2024-07-30. Two-photon decay of para-positronium within a composite approach. https://arxiv.org/abs/2407.20834

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