Constraining anomalous Higgs boson couplings to the heavy flavor fermions using matrix element techniques

TL;DR

This paper develops advanced matrix element techniques to analyze anomalous Higgs couplings to heavy fermions, enhancing sensitivity in multiple Higgs production and decay channels at the LHC.

Contribution

It extends the MELA technique with NLO QCD accuracy and implements new analysis tools within the JHU framework for improved Higgs coupling measurements.

Findings

Enhanced sensitivity to anomalous couplings in Higgs processes.

Validated MELA performance with NLO QCD simulations.

Projected constraints for LHC Run III measurements.

Abstract

In this paper we investigate anomalous interactions of the Higgs boson with heavy fermions, employing shapes of kinematic distributions. We study the processes $pp \to t\bar{t} + H$, $b\bar{b} + H$, $tq+H$, and $pp \to H\to\tau^+\tau^-$, and present applications of event generation, re-weighting techniques for fast simulation of anomalous couplings, as well as matrix element techniques for optimal sensitivity. We extend the MELA technique, which proved to be a powerful matrix element tool for Higgs boson discovery and characterization during Run I of the LHC, and implement all analysis tools in the JHU generator framework. A next-to-leading order QCD description of the $pp \to t\bar{t} + H$ process allows us to investigate the performance of MELA in the presence of extra radiation. Finally, projections for LHC measurements through the end of Run III are presented.