Probing composite Higgs boson substructure at the HL-LHC

TL;DR

This paper investigates the potential to detect the substructure of a composite Higgs boson at the HL-LHC by analyzing how its momentum-dependent couplings affect kinematic distributions, especially in the Z*H channel.

Contribution

It introduces form factors to model the Higgs' composite nature and demonstrates their effects on LHC kinematic distributions, offering a new method to probe Higgs substructure.

Findings

Form factors significantly alter differential distributions.

The Z*H channel is sensitive to Higgs substructure.

Probing Higgs compositeness is feasible at HL-LHC.

Abstract

The Higgs boson may well be a composite scalar with a finite extension in space. Owing to the momentum dependence of its couplings the imprints of such a composite pseudo Goldstone Higgs may show up in the tails of various kinematic distributions at the LHC, distinguishing it from an elementary state. From the bottom up we construct the momentum dependent form factors to capture the interactions of the composite Higgs with the weak gauge bosons. We demonstrate their impact in the differential distributions of various kinematic parameters for the $pp\rightarrow Z^*H\rightarrow l^+l^-b\bar{b}$ channel. We show that this channel can provide an important handle to probe the Higgs' substructure at the HL-LHC.