Precision measurement of the hadronic contribution to the muon anomalous magnetic moment

Le résumé fourni par la source

We report on a precision measurement of the cross section for the reaction ${e}^{+}{e}^{\ensuremath{-}}\ensuremath{\rightarrow}{\ensuremath{\pi}}^{+}{\ensuremath{\pi}}^{\ensuremath{-}}$ in the mass range $0.30<{M}_{\ensuremath{\pi}\ensuremath{\pi}}<1.00\text{ }\text{ }\mathrm{GeV}/{c}^{2}$ with the initial state radiation (ISR) method, using $817\text{ }\text{ }{\mathrm{pb}}^{\ensuremath{-}1}$ of data at ${e}^{+}{e}^{\ensuremath{-}}$ center-of-mass energies near 3.77 GeV and $586\text{ }\text{ }{\mathrm{pb}}^{\ensuremath{-}1}$ of data at ${e}^{+}{e}^{\ensuremath{-}}$ center-of-mass energies near 4.17 GeV, collected with the CLEO-c detector at the CESR ${e}^{+}{e}^{\ensuremath{-}}$ collider at Cornell University. The integrated cross sections in the range $0.30<{M}_{\ensuremath{\pi}\ensuremath{\pi}}<1.00\text{ }\text{ }\mathrm{GeV}/{c}^{2}$ for the process ${e}^{+}{e}^{\ensuremath{-}}\ensuremath{\rightarrow}{\ensuremath{\pi}}^{+}{\ensuremath{\pi}}^{\ensuremath{-}}$ are determined with a statistical uncertainty of 0.7% and a systematic uncertainty of 1.6%. The leading-order hadronic contribution to the muon anomalous magnetic moment calculated using these measured ${e}^{+}{e}^{\ensuremath{-}}\ensuremath{\rightarrow}{\ensuremath{\pi}}^{+}{\ensuremath{\pi}}^{\ensuremath{-}}$ cross sections in the range ${M}_{\ensuremath{\pi}\ensuremath{\pi}}=0.30$ to $1.00\text{ }\text{ }\mathrm{GeV}/{c}^{2}$ is calculated to be $(500.6\ifmmode\pm\else\textpm\fi{}3.6(\mathrm{stat})\ifmmode\pm\else\textpm\fi{}8.0(\mathrm{syst}))\ifmmode\times\else\texttimes\fi{}{10}^{\ensuremath{-}10}$.

Ce résumé expose les affirmations des auteurs. BNTIC ne l’interprète pas comme une validation indépendante des résultats.