Perturbative unitarity constraints on generic Yukawa interactions

Abstract

We study perturbative unitarity constraints on generic Yukawa interactions where the involved fields have arbitrary quantum numbers under an ${\prod }_{i}SU(N_i)\otimes U(1)$ group. We derive compact expressions for the bounds on the Yukawa couplings for the cases where the fields transform under the trivial, fundamental or adjoint representation of the various $SU(N)$ factors. We apply our results to specific models formulated to explain the anomalous measurements of $(g-2{)}_{\mu }$ and of the charged- and neutral-current decays of the $B$ mesons. We show that, while these models can generally still explain the observed experimental values, the required Yukawa couplings are pushed at the edge of the perturbative regime.

50 pages, 10 figures; typos fixed, references added, matches published version

References in corpus (22)

• Test of lepton universality using $B^{+}\to K^{+}{\ell }^{+}{\ell }^{-}$ decays
• B-physics anomalies: a guide to combined explanations
• Gauge leptoquark as the origin of B-physics anomalies
• Baryon Number and Lepton Universality Violation in Leptoquark and Diquark Models
• Leptoquark model to explain the $B$-physics anomalies, $R_K$ and $R_D$
• Leptoquark Flavor Patterns & B Decay Anomalies
• Lepton universality violation and lepton flavor conservation in $B$-meson decays
• $\Delta M_s$ theory precision confronts flavour anomalies
• What is the scale of new physics behind the $B$-flavour anomalies?
• The role of the $S_3$ GUT leptoquark in flavor universality and collider searches
• Expectations for the muon g-2 in simplified models with dark matter
• On the Origin of Neutrino Masses
• Probing low energy scalar leptoquarks by the leptonic $W$ and $Z$ couplings
• Combined explanations of $(g-2{)}_{\mu }$, $R_{D^{(\ast )}}$, $R_{K^{(\ast )}}$ anomalies in a two-loop radiative neutrino mass model
• Unitarity Constraints on Dimension-Six Operators
• Unitarity Constraints on Dimension-six Operators II: Including Fermionic Operators
• A Minimal Explanation of Flavour Anomalies: B-Meson Decays, Muon Magnetic Moment, and the Cabibbo Angle
• Impact of the $b\to sll$ anomalies on dark matter physics
• SU(5) Unification with TeV-scale Leptoquarks
• B anomalies and dark matter: a complex connection
• What is the scale of new physics behind the muon $g-2$?
• Unitarity constraints on ALP interactions