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arXiv · 0906.4331

A precise new KLOE measurement of $|F_π|^2$ with ISR events and determination of $ππ$ contribution to $a_μ$ for $0.592 < M_{ππ} < 0.975$ GeV

Graziano Venanzoni
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Abstract

The KLOE experiment at the DA$Φ$NE $ϕ$-factory has performed a new precise measurement of the pion form factor using Initial State Radiation events, with photons emitted at small polar angle. Results based on an integrated luminosity of 240 pb$^{-1}$ and extraction of the $ππ$ contribution to $a_μ$ in the mass range $0.35< M^2_{ππ}<0.95$ GeV$^2$ are presented. The new value of $a^{ππ}_μ$ has smaller (30%) statistical and systematic error and is consistent with the KLOE published value (confirming the current disagreement between the standard model prediction for $a_μ$ and the measured value).

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Graziano Venanzoni. 2009-06-23. A precise new KLOE measurement of $|F_π|^2$ with ISR events and determination of $ππ$ contribution to $a_μ$ for $0.592 < M_{ππ} < 0.975$ GeV. https://doi.org/10.1063/1.3293895

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