New precise measurement of the $e^{+}{e}^{-}\to {\pi }^{+}{\pi }^{-}(\gamma )$ cross section with BABAR

Abstract

The BABAR experiment participates to the global endeavor for a precise prediction of the anomalous magnetic moment of the muon by evaluating the contribution from hadronic vacuum polarization, in particular through cross section measurements of hadronic final states from $e^{+}{e}^{-}$ collisions. After a first measurement in 2009 of the largest input that comes from the $e^{+}{e}^{-}\to {\pi }^{+}{\pi }^{-}(\gamma )$ cross section, we present preliminary results from a new study on 460 ${\mathrm{fb}}^{-1}$ of BABAR data, involving a blind and independent procedure. The results of the two analyses are shown to be consistent.

5 pages, 6 figures, Presented at the 32nd International Symposium on Lepton Photon Interactions at High Energies, Madison, Wisconsin, USA, August 25-29, 2025