Speaker
Description
We present the first search for Higgs boson pair production in association with top quarks ($t\bar{t}HH$), using proton–proton collision data recorded by the ATLAS detector, corresponding to the full Run 2 and partial Run 3 datasets. The $t\bar{t}HH$ process is the third most significant production mode for Higgs boson pairs at the LHC and offers direct sensitivity to the anomalous $t\bar{t}HH$ quartic interaction. This analysis aims to contribute to the constraint of the $c(t\bar{t}HH)$ parameter.
Events are selected and categorized into three final states, each targeting different $t\bar{t}HH$ decay channels. Events with at least one charged lepton and multiple jets are divided into single-lepton and multi-lepton final states, based on the number and charge of leptons. Events containing photons are categorized into the $b\bar{b}\gamma \gamma$ final state.
Dedicated control regions are used to constrain the dominant backgrounds. A transformer-based machine learning model is employed to enhance discrimination between signal and background events.
| Field | ATLAS |
|---|
