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arXiv · 1701.01837

Photon radiation in $e^+e^-\to$ hadrons at low energies with CARLOMAT 3.1

Fred Jegerlehner·Karol Kolodziej
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Abstract

We present a sample of results for the cross sections of several processes of low energetic $e^+e^-$ annihilation into final states containing pions accompanied by one or two photons, or a light lepton pair. The results, which have been obtained with a new version of a multipurpose Monte Carlo program CARLOMAT, labelled 3.1, demonstrate new capabilities of the program which, among others, include a possibility of taking into account either the initial or final state radiation separately, or both at a time, and a possibility of inclusion of the electromagnetic charged pion form factor for processes with charged pion pairs. We also discuss some problems related to the $U(1)$ electromagnetic gauge invariance.

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Fred Jegerlehner, Karol Kolodziej. 2017-04-25. Photon radiation in $e^+e^-\to$ hadrons at low energies with CARLOMAT 3.1. https://doi.org/10.1140/epjc%2Fs10052-017-4816-7

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