$\tau$ lepton mass measurement at BESIII

J. Y. Zhang

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arXiv · 1812.10056

$\tau$ lepton mass measurement at BESIII

J. Y. Zhang

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Abstract

In order to obtain the mass of $\tau$ lepton at BESIII precisely, a beam energy measurement system was built at BEPCII. A scenario for high precision $\tau$ mass measurement was put forth before data taken. More than 130 $pb^{-1}$ $\tau$ mass scan data were collected in April 2018, and the uncertainty of $m_{\tau}$ is expected to be less than 100 keV.

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J. Y. Zhang. 2018-12-25. $\tau$ lepton mass measurement at BESIII. https://arxiv.org/abs/1812.10056

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