Flavour-Changing Decays of a 125 GeV Higgs-like Particle

Abstract

The ATLAS and CMS experiments at the LHC have reported the observation of a possible excess of events corresponding to a new particle $h$ with mass $\sim 125$ GeV that might be the long-sought Higgs boson, or something else. Decyphering the nature of this possible signal will require constraining the couplings of the $h$ and measuring them as accurately as possible. Here we analyze the indirect constraints on flavour-changing $h$ decays that are provided by limits on low-energy flavour-changing interactions. We find that indirect limits in the quark sector impose such strong constraints that flavour-changing $h$ decays to quark-antiquark pairs are unlikely to be observable at the LHC. On the other hand, the upper limits on lepton-flavour-changing decays are weaker, and the experimental signatures less challenging. In particular, we find that either $\mathcal{B}(h\to \tau \bar{\mu }+\bar{\mu }\tau )$ or $\mathcal{B}(h\to \tau \bar{e}+\bar{e}\tau )$ could be $\mathcal{O}(10)$, i.e., comparable to $\mathcal{B}(h\to {\tau }^{+}{\tau }^{-})$ and potentially observable at the LHC.

8 pages, 1 figure. v2: a few typos and numerical errors corrected, discussion of 2-loop bounds added, extended list of references, conclusions unchanged

References in corpus (23)

• Theory and phenomenology of two-Higgs-doublet models
• Combined results of searches for the standard model Higgs boson in pp collisions at sqrt(s) = 7 TeV
• Combined search for the Standard Model Higgs boson using up to 4.9 fb-1 of pp collision data at sqrt(s) = 7 TeV with the ATLAS detector at the LHC
• Light scalar at LHC: the Higgs or the dilaton?
• Flavour physics of leptons and dipole moments
• New limit on the lepton-flavour violating decay mu -> e gamma
• Search for the Standard Model Higgs boson in the diphoton decay channel with 4.9 fb-1 of pp collisions at sqrt(s) = 7 TeV with ATLAS
• Search for the standard model Higgs boson decaying into two photons in pp collisions at sqrt(s)=7 TeV
• Search for neutral Higgs bosons decaying to tau pairs in pp collisions at sqrt(s) = 7 TeV
• Higgs-dependent Yukawa couplings
• Higgs Mediated FCNC's in Warped Extra Dimensions
• Search for the Standard Model Higgs boson in the decay channel H->ZZ(*)->4l with 4.8 fb-1 of pp collision data at sqrt(s) = 7 TeV with ATLAS
• Composite Higgs-Mediated FCNC
• Search for the standard model Higgs boson decaying to a W pair in the fully leptonic final state in pp collisions at sqrt(s) = 7 TeV
• Search for the standard model Higgs boson in the decay channel H to ZZ to 4 leptons in pp collisions at sqrt(s) = 7 TeV
• Higgs-induced lepton flavor violation
• Search for the standard model Higgs boson decaying to bottom quarks in pp collisions at sqrt(s) = 7 TeV
• Standard Model couplings and collider signatures of a light scalar
• Minimal violation of flavour and custodial symmetries in a vectophobic Two-Higgs-Doublet-Model
• Search for the standard model Higgs boson in the H to ZZ to 2l 2nu channel in pp collisions at sqrt(s) = 7 TeV
• Search for the rare decays Bs -> mu+ mu- and B0 -> mu+ mu-
• Search for the standard model Higgs boson in the H to ZZ to ll tau tau decay channel in pp collisions at sqrt(s)=7 TeV
• Effective Yukawa couplings and flavor-changing Higgs boson decays at linear colliders

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• Explaining $h\to {\mu }^{\pm }{\tau }^{\mp }$, $B\to K^{\ast }{\mu }^{+}{\mu }^{-}$ and $B\to K{\mu }^{+}{\mu }^{-}/B\to K{e}^{+}{e}^{-}$ in a two-Higgs-doublet model with gauged $L_{\mu }-L_{\tau }$
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• Constraints on CP-violating Higgs couplings to the third generation
• Testing sterile neutrino extensions of the Standard Model at future lepton colliders
• Lepton Flavor Violation in the Standard Model with general Dimension-Six Operators
• A Higgslike Dilaton
• Imprints of massive inverse seesaw model neutrinos in lepton flavor violating Higgs boson decays
• Constrained MSSM favoring new territories: The impact of new LHC limits and a 125 GeV Higgs boson
• Search for lepton-flavour-violating decays of the Higgs and $Z$ bosons with the ATLAS detector
• Higgs $\to \mu \tau$ in Abelian and Non-Abelian Flavor Symmetry Models
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• Flavour Changing Higgs Couplings in a Class of Two Higgs Doublet Models
• Lepton flavor violation in low-scale seesaw models: SUSY and non-SUSY contributions
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• A $L_{\mu }-L_{\tau }$ theory of Higgs flavor violation and $(g-2{)}_{\mu }$
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• Leptoquark explanation of $h\to \mu \tau$ and muon $(g-2)$
• Non-decoupling SUSY in LFV Higgs decays: a window to new physics at the LHC
• What if BR(h-->μμ)/BR(h-->ττ) does not equal m_μ^2/m_τ^2?
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• Lepton flavor violating Higgs boson decays in seesaw models: new discussions
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• Collider Constraints on Lepton Flavor Violation in the 2HDM
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• Machine learning the trilinear and light-quark Yukawa couplings from Higgs pair kinematic shapes
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