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arXiv · 1705.10365

From Hadronic Cross Section to the measurement of the Vacuum Polarization at KLOE: a fascinating endeavour

Graziano Venanzoni
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Abstract

The KLOE experiment at the $\phi-factory$ DA$\Phi$NE in Frascati is the first to have employed Initial State Radiation (ISR) to precisely determine the $e^+e^-\to\pi^+\pi^-(\gamma)$ cross section below 1 GeV. Such a measurement is particularly important to test the Standard Model (SM) calculation for the $(g-2)$ of the muon, where a long standing 3$\sigma$ discrepancy is observed. I will review the ISR activity in KLOE in the last 18 years from the measurement of the hadronic cross section to the first direct determination of the time-like complex running $\alpha(s)$ in the region below 1 GeV.

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Graziano Venanzoni. 2017-05-29. From Hadronic Cross Section to the measurement of the Vacuum Polarization at KLOE: a fascinating endeavour. https://doi.org/10.1051/epjconf%2F201816600021

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