Higgs boson production via vector-like top-partner decays: diphoton or multilepton plus multijets channels at the LHC

TL;DR

This paper proposes a minimal model with vector-like quarks that suppresses standard Higgs production at the LHC, and explores Higgs discovery via heavy top-partner decays into diphoton or multilepton channels, especially relevant for a 125 GeV Higgs.

Contribution

The paper introduces a minimal vector-like quark model that suppresses gluon fusion and enables Higgs detection through top-partner decays at the LHC, providing new search strategies.

Findings

Higgs production via top-partner decay can be significant despite suppressed gluon fusion.

Higgs can be discovered through diphoton or ZZ decay channels in this model.

The model is compatible with current experimental constraints and recent Higgs hints.

Abstract

We first build a minimal model of vector-like quarks where the dominant Higgs boson production process at LHC -- the gluon fusion -- can be significantly suppressed, being motivated by the recent stringent constraints from the search for direct Higgs production over a wide Higgs mass range. Within this model, compatible with the present experimental constraints on direct Higgs searches, we demonstrate that the Higgs ($h$) production via a heavy vector-like top-partner ($t_2$) decay, $pp \to t_2 \bar t_2$, $t_2\to t h$, allows to discover a Higgs boson at the LHC and measure its mass, through the decay channels $h\to \gamma\gamma$ or $h\to ZZ$. We also comment on the recent hint in LHC data from a possible $\sim 125$ GeV Higgs scalar, in the presence of heavy vector-like top quarks.