Lepton Flavor and Nonuniversality from Minimal Composite Higgs Setups

Area of Science:

• High Energy Physics
• Particle Physics
• Beyond Standard Model Physics

Background:

• The Standard Model of particle physics has limitations in explaining flavor anomalies.
• Composite Higgs models offer a framework to address these limitations.
• The LHCb experiment has observed anomalies in lepton flavor universality, particularly in the R_K ratio.

Purpose of the Study:

• To propose a new class of minimal models for lepton flavor within the composite Higgs framework.
• To investigate the phenomenological consequences of these models and their agreement with experimental data.
• To explain the observed anomaly in R_K and other lepton flavor universality violations.

Main Methods:

• Developing a minimal set of models for lepton flavor in the composite Higgs scenario.
• Unifying right-handed leptons to create a predictive framework.
• Analyzing the implications for neutral current interactions and flavor-changing neutral currents.

Main Results:

• The proposed models naturally lead to violations of lepton-flavor universality in neutral current interactions.
• The anomaly in R_K = B(B→Kμ^{+}μ^{-})/B(B→Ke^{+}e^{-}) can be successfully addressed.
• The models satisfy other constraints from quark- and lepton-flavor physics.
• A powerful flavor protection mechanism is implemented, minimizing new flavor-changing neutral currents.

Conclusions:

• The minimal composite Higgs models presented provide a compelling explanation for lepton flavor anomalies.
• The unification of right-handed leptons leads to a predictive scenario consistent with current experimental observations.
• These models weaken the need for ultralight top partners by linking Higgs mass corrections to neutrino masses.