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Search for Lepton-Flavor and Lepton-Number Violation in the Decay tau->lhh

BaBar Collaboration·B. Aubert
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Abstract

A search for lepton-flavor and lepton-number violation in the decay of the tau lepton into one charged lepton and two charged hadrons is performed using 221.4 $\mathrm{fb}^{-1}$ of data collected at an $e^+e^-$ center-of-mass energy of 10.58 GeV with the BaBar detector at the PEP-II storage ring. In all 14 decay modes considered, the observed data are compatible with background expectations, and upper limits are set in the range ${\cal B}(τ\to\ell hh')<(0.7-4.8)\times 10^{-7}$ at 90% confidence level.

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BaBar Collaboration, B. Aubert. 2005-06-27. Search for Lepton-Flavor and Lepton-Number Violation in the Decay tau->lhh. https://doi.org/10.1103/physrevlett.95.191801

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