Composite Leptons at the LHC

TL;DR

This paper explores the possibility that W, Z, and Higgs bosons are composite particles made of subconstituents, using phenomenological models to analyze spin interactions and estimate related mass splittings, with implications for lepton states.

Contribution

It introduces a phenomenological model to relate spin splittings of composite bosons to subconstituent interactions and applies this to estimate lepton state splittings.

Findings

Spin splitting between W/Z and Higgs states can be used to infer hyperfine interaction strength.

The model suggests possible mass splittings in the lepton sector based on hyperfine interactions.

Analogies with the SU(6) quark model support the approach.

Abstract

In some models of electro-weak interactions the W and Z bosons are considered composites, made up of spin-one-half subconstituents. In these models a spin zero counterpart of the W and Z boson naturally appears, whose higher mass can be attributed to a particular type of hyperfine spin interaction among the various subconstituents. Recently it has been argued that the scalar state could be identified with the newly discovered Higgs (H) candidate. Here we use the known spin splitting between the W/Z and H states to infer, within the framework of a purely phenomenological model, the relative strength of the spin-spin interactions. The results are then applied to the lepton sector, and used to crudely estimate the relevant spin splitting between the two lowest states. Our calculations in many ways parallels what is done in the SU(6) quark model, where most of the spin splittings between the lowest lying baryon and meson states are reasonably well accounted for by a simple color hyperfine interaction, with constituent (color-dressed) quark masses.