Lepton-flavour violating decays in theories with dimension 6 operators

Abstract

Despite a large experimental effort, so far no evidence for flavour-violating decays of charged leptons such as $l_i\to l_j\gamma$ and $l_i\to l_j{l}_k{l}_k$ has been found. The absence of a signal puts very severe constraints on many extensions of the Standard Model. Here we apply a model independent approach by studying such decays in the Standard Model effective field theory. Going beyond leading order in the Standard Model couplings and considering all dimension 6 operators that might lead to lepton-flavour violation, we are able to extract limits on a large number of Wilson coefficients of such operators. We are also able to compare the impact of particular searches and find, for example, that flavour-violating decays of the $Z$-boson $Z\to \mu e$ are much more constrained from low-energy experiments $\mu \to e\gamma$ than from the limits of current and future direct searches at high energy.

7 pages, 5 Tables; to appear in the Proceedings of the FCCP2015 Workshop

References in corpus (17)

• Observation of a new particle in the search for the Standard Model Higgs boson with the ATLAS detector at the LHC
• Observation of a new boson at a mass of 125 GeV with the CMS experiment at the LHC
• Addressing the LHC flavour anomalies with horizontal gauge symmetries
• Search for lepton-flavour-violating decays of the Higgs boson
• Extending the Standard Model Effective Field Theory with the Complete Set of Dimension-7 Operators
• Lepton flavor violation in low-scale seesaw models: SUSY and non-SUSY contributions
• Indirect searches for sterile neutrinos at a high-luminosity Z-factory
• Explaining the CMS Higgs flavor violating decay excess
• New Physics Models Facing Lepton Flavor Violating Higgs Decays at the Percent Level
• Lepton-flavor-violating Higgs decay $h\to \mu \tau$ and muon anomalous magnetic moment in a general two Higgs doublet model
• Search for the lepton flavor violating decay $Z\to e\mu$ in pp collisions at $\sqrt{s}$ = 8 TeV with the ATLAS detector
• The $\mu \to e\gamma$ decay in a systematic effective field theory approach with dimension 6 operators
• Improved predictions for $\mu \to e$ conversion in nuclei and Higgs-induced lepton flavor violation
• The model-discriminating power of lepton flavor violating tau decays
• Lepton Flavor Violation in Flavored Gauge Mediation
• Flavor and CP violation in Higgs decays
• Understanding the correlation between $(g-2{)}_{\mu }$ and $\mu \to e\gamma$ in the MSSM

Cited by in corpus (8)

• The SMEFTsim package, theory and tools
• Renormalisation-group improved analysis of $\mu \to e$ processes in a systematic effective-field-theory approach
• Reactor neutrino oscillations as constraints on Effective Field Theory
• Charged lepton flavor violating Higgs decays at future $e^{+}{e}^{-}$ colliders
• Next-to-leading order prediction for the decay $\mu \to e(e^{+}{e}^{-})\nu \bar{\nu }$
• Minimal Models of Loop-Induced Higgs Lepton Flavor Violation
• Gearing up for the next generation of LFV experiments, via on-shell methods
• Effective-field theories for charged lepton flavour violation