New precise determination of the \tau lepton mass at KEDR detector

KEDR collaboration; V. V. Anashin; V. M. Aulchenko; E. M. Baldin

doi:10.1016/j.nuclphysbps.2007.02.104

New precise determination of the \tau lepton mass at KEDR detector

High Energy Physics - Experiment 2008-11-26 v1

Authors: KEDR collaboration , V. V. Anashin , V. M. Aulchenko , E. M. Baldin

View on arXiv ↗ PDF ↗ DOI ↗

Abstract

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

Keywords

tau lepton mass KEDR detector VEPP-4M collider cross section threshold

Cite

@article{arxiv.hep-ex/0611046,
  title  = {New precise determination of the \tau lepton mass at KEDR detector},
  author = {KEDR collaboration and V. V. Anashin and V. M. Aulchenko and E. M. Baldin},
  journal= {arXiv preprint arXiv:hep-ex/0611046},
  year   = {2008}
}