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arXiv · 2006.11082

Electron-positron annihilation to photons at $O(\alpha^3)$ revisited

Roman N. Lee
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Abstract

We apply the modern multiloop methods to the calculation of the total cross sections of electron-positron annihilation to 2 and 3 photons exactly in $s/m^2$ with the accuracy $O(\alpha^3)$. Examining the asymptotics of our results, we find agreement with Ref. [Andreassi_et_al_1962] and discover mistakes in the results of Refs. [Eidelman&Kuraev_1978,Berends&Kleiss_1981]. This mistake is due to the terms, omitted in differential cross section in Refs. \[Eidelman&Kuraev_1978,Berends&Kleiss_1981], which are peaked in the kinematic region with all three photons being quasi-parallel to the collision axis. After restoring these terms, we find an agreement of the corrected result of Ref. [Berends&Kleiss_1981] with our result.

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Roman N. Lee. 2020-06-19. Electron-positron annihilation to photons at $O(\alpha^3)$ revisited. https://doi.org/10.1016/j.nuclphysb.2020.115200

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