Measuring the signal strength in ttH with H->bb

TL;DR

This paper presents a detailed analysis of measuring the Higgs boson signal strength in ttH production with H->bb decay at the LHC, utilizing jet substructure techniques across various phase space regions to improve sensitivity.

Contribution

It introduces a comprehensive approach combining multiple phase space regions and jet substructure methods to enhance the measurement precision of ttH(bb) processes.

Findings

Potential to measure 20% deviations in signal strength with 3 ab^{-1} data

Use of boosted phase space regions improves background suppression

Combining regions increases measurement sensitivity

Abstract

A precise measurement of the Higgs boson couplings to bottom and top quarks is of paramount importance during the upcoming LHC runs. We present a comprehensive analysis for the Higgs production process in association with a semi-leptonically decaying top-quark pair and subsequent Higgs boson decay into bottom quarks. Due to the highly complex final state and large Standard Model backgrounds, measuring the signal strength in this process is known to be challenging. To maximise the sensitivity, we analyse different, statistically independent, phase space regions, where one or more of the heavy resonances are boosted. This allows us to employ jet substructure techniques, which help to reduce large tt+X backgrounds. We find that combining several ttH(bb) phase space regions will allow one to measure deviations of the Standard Model signal strength of order 20% with 3 ab^{-1}.