Measurement of the muon anomalous magnetic moment a_mu is particularly sensitive to physics beyond the standard model (SM). At present, the experimental value is 3.2-3.6 standard deviations above the SM predictions and provides one of the strongest hints of new physics. Among several hadronic contributions the tree-pion channel accounts for the second- largest contribution to both the value of a_mu and the corresponding uncertainty.
In this project, the three-pion production in electron-positron annihilations is studied using the initial state radiation process at center-of mass energy 1.019 GeV. An integrated luminosity 1.62 fb⁻1 data sample collected during period 2004-2005 at KLOE is used in this analysis. Preliminary results from the KLOE experiment including determination of line shape in omega-mass region will be presented and discussed in this seminar.