Search for τ^-→ μ^-μ⁺μ^- decays at the LHCb experiment with Run 2 data

2026/01/28 by LHCb collaboration, R. Aaij, A. S. W. Abdelmotteleb +1188 · 2 voices
#hep-ex

paper · pdf

Abstract

A search for the lepton-flavour-violating decay τ^-→ μ^-μ⁺μ^- is carried out using data collected by the LHCb experiment between 2016 and 2018 in proton-proton collisions at the LHC at a centre-of-mass energy of 13 TeV, corresponding to an integrated luminosity of 5.4 fb^-1. An upper limit of 1.9 (2.3)× 10^-8 is set at the 90% (95%) confidence level on the branching fraction of the decay.

Citations

• The LHCb Stripping Project: Sustainable Legacy Data Processing for High-Energy Physics
• The RooStats Project

Discussions

• Search for τ⁻→μ⁻μ⁻μ⁺ decays at the LHCb experiment with Run 2 data arxiv.org/abs/2601.20785 - An upper limit of 1.9(2.3)×10⁻⁸ is set at the 90% (95%) confidence level on the branching fraction of the [bsky, 5 points, 0 comments]
• #LHCbpaper: Search for the τ⁻ → μ⁻ μ⁺μ⁻ decays at LHCb Experiment with Run2 data (arXiv:2601.20785) https://arxiv.org/abs/2601.20785 [bsky, 2 points, 0 comments]

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