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arXiv · hep-ex/0611046

New precise determination of the τlepton mass at KEDR detector

KEDR collaboration·V. V. Anashin·V. M. Aulchenko·E. M. Baldin
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Abstract

The status of the experiment on the precise $τ$ lepton mass measurement running at the VEPP-4M collider with the KEDR detector is reported. The mass value is evaluated from the $τ^+τ^-$ cross section behaviour around the production threshold. The preliminary result based on 6.7 pb$^{-1}$ of data is $m_τ=1776.80^{+0.25}_{-0.23} \pm 0.15$ MeV. Using 0.8 pb$^{-1}$ of data collected at the $ψ'$ peak the preliminary result is also obtained: $Γ_{ee}B_{ττ}(ψ') = 7.2 \pm 2.1$ eV.

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KEDR collaboration, V. V. Anashin, V. M. Aulchenko, E. M. Baldin. 2006-11-27. New precise determination of the τlepton mass at KEDR detector. https://doi.org/10.1016/j.nuclphysbps.2007.02.104

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