The KLOE experiment at the DA$\Phi$NE $\phi$-factory has performed a new precise measurement of the pion form factor using Initial State Radiation events. Results based on an integrated luminosity of 240 pb$^{ -1}$ and extraction of the $\pi\pi$ contribution to $a_\mu$ in the mass range $0.35< M^2_{ \pi\pi}<0.95$ GeV$^2$ are presented. The new value of $a^{ \pi\pi}_\mu$ has smaller statistical and systematic error and is consistent with the KLOE published value (confirming the current disagreement between the Standard Model prediction for $a_\mu$ and the measured value).

Categories: hep-ex

Hadronic cross section measurements and contribution to $(g-2)_\mu$ with KLOE