Search for $t\bar{t}H$ production at the LHC

TL;DR

This paper reviews searches for the associated production of the Higgs boson with top quark pairs at the LHC, analyzing multiple decay channels and collision energies, with some indications of excess events.

Contribution

It compiles and compares results from ATLAS and CMS searches for t-tbar-H production across various decay modes and energies, highlighting potential signals and background expectations.

Findings

No significant excess in b-quark and photon channels.

CMS observes a 3-sigma excess in multi-lepton channel.

Results constrain Higgs-top coupling measurements.

Abstract

The searches for the production of the Higgs boson associated with a pair of top quarks in the ATLAS and CMS experiments are presented. The searches use a range of final states sensitive to the Higgs boson decaying into b-quark pairs, pairs of vector bosons, pairs of taus and pairs of photons. All the searches use pp collision data at $\sqrt{s} = 8$ TeV collected with the ATLAS and CMS detectors at the LHC in 2012 and some analyses also include the data collected at $\sqrt{s} = 7$ TeV in 2011. The searches in the $b\bar{b}$ and $\gamma\gamma$ channels observe no excess of events relative to the background expectation, while the CMS search using multi-lepton events observes an excess of slightly more than 3 standard deviations over the background expectation.