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arXiv · 1712.04530

Precision Measurement of the Hadronic Contribution to the Muon Anomalous Magnetic Moment

Abstract

We report on a precision measurement of the cross section for the reaction $e^+e^-\toπ^+π^-$ in the mass range $0.30<M_{ππ}<1.00$ GeV with the initial state radiation (ISR) method, using 817 pb$^{-1}$ of data at $e^+e^-$ center-of-mass energies near 3.77 GeV and 586 pb$^{-1}$ of data at $e^+e^-$ center-of-mass energies near 4.17 GeV, collected with the CLEO-c detector at the CESR $e^+e^-$ collider at Cornell University. The integrated cross sections in the range $0.30<M_{ππ}<1.00$ GeV for the process $e^+e^-\toπ^+π^-$ are determined with a statistical uncertainty of $0.7\%$ and a systematic uncertainty of $1.5\%$. The leading-order hadronic contribution to the muon anomalous magnetic moment calculated using these measured $e^+e^-\toπ^+π^-$ cross sections in the range $M_{ππ}=0.30$ to 1.00 GeV is calculated to be $(500.4\pm3.6 (\mathrm{stat})\pm 7.5(\mathrm{syst}))\times10^{-10}$.

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BibTeXRIS

T. Xiao, S. Dobbs, A. Tomaradze, Kamal K. Seth, G. Bonvicini. 2017-12-12. Precision Measurement of the Hadronic Contribution to the Muon Anomalous Magnetic Moment. https://doi.org/10.1103/physrevd.97.032012

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