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arXiv · 1612.08162

Measurement of the $π^0$ electromagnetic transition form factor slope

The NA62 collaboration
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Abstract

The NA62 experiment collected a large sample of charged kaon decays in 2007 with a highly efficient trigger for decays into electrons. A measurement of the $π^0$ electromagnetic transition form factor slope parameter from $1.11\times10^{6}$ fully reconstructed $K^\pm \to π^\pm π^0_D, π^0_D \to e^+ e^-γ$ events is reported. The measured value $a = (3.68 \pm 0.57)\times10^{-2}$ is in good agreement with theoretical expectations and previous measurements, and represents the most precise experimental determination of the slope in the time-like momentum transfer region.

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The NA62 collaboration. 2017-02-15. Measurement of the $π^0$ electromagnetic transition form factor slope. https://doi.org/10.1016/j.physletb.2017.02.042

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