Hadronic τ Decays as New Physics Probes in the LHC Era

Research output: Contribution to journalArticle


We analyze the sensitivity of hadronic τ decays to nonstandard interactions within the model-independent framework of the standard model effective field theory. Both exclusive and inclusive decays are studied, using the latest lattice data and QCD dispersion relations. We show that there are enough theoretically clean channels to disentangle all the effective couplings contributing to these decays, with the τ→ππντ channel representing an unexpected powerful new physics probe. We find that the ratios of nonstandard couplings to the Fermi constant are bound at the subpercent level. These bounds are complementary to the ones from electroweak precision observables and pp→τντ measurements at the LHC. The combination of τ decay and LHC data puts tighter constraints on lepton universality violation in the gauge boson-lepton vertex corrections.


External organisations
  • Los Alamos National Laboratory
  • University of Paris-Sud
  • CERN
  • University of Valencia
Research areas and keywords

Subject classification (UKÄ) – MANDATORY

  • Subatomic Physics
Original languageEnglish
Article number221801
JournalPhysical Review Letters
Issue number22
Publication statusPublished - 2019 Jun 7
Publication categoryResearch