Lepton-flavour violating decays in theories with dimension 6 operators
TLDR
In this paper, the authors apply a model independent approach by studying such decays in the Standard Model effective field theory, and they are able to extract limits on a large number of Wilson coefficients of such 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.read more
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Model independent constraints on four-lepton operators
Adam Falkowski,Kin Mimouni +1 more
TL;DR: In this article, the confidence intervals for Wilson coefficients of 16 lepton-flavor conserving 4-lepton operators with dimension-6 operators are analyzed. But the analysis does not rely on any assumptions about the flavor structure of the dimension-six operators.
Journal ArticleDOI
Model independent constraints on four-lepton operators
Adam Falkowski,Kin Mimouni +1 more
TL;DR: In this article, the confidence intervals for Wilson coefficients of 16 lepton-flavor conserving four-lepton operators with dimension-6 operators are analyzed. But the analysis does not rely on any assumptions about the flavor structure of the dimension-six operators.
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On the exotic Higgs decays in effective field theory
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