Probing top-partners in Higgs + jets

TL;DR

This paper demonstrates that analyzing Higgs plus jets production at the LHC can reveal properties of top-partners, overcoming previous cancellations that limited information from Higgs couplings alone.

Contribution

It introduces a method to probe top-partner masses and couplings using differential distributions in Higgs plus jets, especially the jet transverse momentum, at the 14 TeV LHC.

Findings

Differential distributions are sensitive to top-partner properties.

300 fb^{-1} of data can exclude certain top-partner mixing angles.

The method extends reach to top-partners above 2 TeV.

Abstract

Fermionic top-partners arise in models such as Composite Higgs and Little Higgs. They modify Higgs properties, in particular how the Higgs couples to top quarks. Alas, there is a low-energy cancellation acting in the coupling of the Higgs boson to gluons and photons. As a result of this cancellation, no information about the spectrum and couplings of the top-partners can be obtained in gluon fusion to Higgs, just the overall new physics scale. In this paper we show that this is not the case when hard radiation is taken into account. Indeed, differential distributions in Higgs plus jets are sensitive to the top-partner mass and coupling to the Higgs. We exploit the transverse momentum distribution of the hard jet to obtain limits on the top-partners in the 14 TeV LHC run, finding that 300 ifb of data of 14 TeV LHC are sufficient to rule out top-sector mixing angles $\sin^2 (\theta_R)$ > 0.05 for top-partners with masses from 300 GeV to above 2 TeV.