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arXiv · 1410.4327

$\eta$ and $\eta'$ transition form factors from Pad\'e approximants

Pablo Sanchez-Puertas·Pere Masjuan
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Abstract

We employ a systematic and model-independent method to extract, from space- and time-like data, the $\eta$ and $\eta'$ transition form factors (TFFs) obtaining the most precise determination for their low-energy parameters and discuss the $\Gamma_{\eta\rightarrow\gamma\gamma}$ impact on them. Using TFF data alone, we also extract the $\eta-\eta'$ mixing parameters, which are compatible to those obtained from more sophisticated and input-demanding procedures.

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Pablo Sanchez-Puertas, Pere Masjuan. 2014-10-16. $\eta$ and $\eta'$ transition form factors from Pad\'e approximants. https://doi.org/10.1051/epjconf%2F20148105025

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