A precise KLOE measurement of σ(e+e−→π+π−) and extraction of between 0.35 and 0.95 GeV2

The KLOE Experiment at the ϕ-factory DAΦNE has measured the cross section σ(e+e−→π+π−γ(γ)) requiring photon emission at small polar angle. Using a theoretical radiator function, we extract the cross section σ(e+e−→π+π−) and obtain the ππ contribution to the muon anomalous magnetic moment, , for values of between 0.35 and 0.95 GeV2. Results presented come from the analysis of 240 pb−1 collected in 2002, with improved systematic uncertainty with respect to the published KLOE analysis.