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arXiv · 1811.09408

Tau-lepton Physics at the FCC-ee circular e$^+$e$^-$ Collider

Mogens Dam
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Abstract

The future FCC-ee collider is designed to deliver $\mathrm{e^+e^-}$ collisions to study with ultimate precision the Z, W, and Higgs bosons, and the top quark. In a high-statistics scan around the Z pole, $1.3\times 10^{11}$ events $\mathrm{Z}\toττ$ will be produced, the largest sample of $ττ$ events foreseen at any lepton collider. With their large boost, $τ$ leptons from Z decays are particularly well suited for precision measurements. The focus of this report is on tests of lepton universality from precision measurement of $\boldsymbolτ$ properties and on tests of charged lepton flavour violation in Z decays and in $τ$ decays. In both of these areas, FCC-ee promises sensitivities well beyond present experimental limits.

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Mogens Dam. 2018-12-17. Tau-lepton Physics at the FCC-ee circular e$^+$e$^-$ Collider. https://arxiv.org/abs/1811.09408

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