Speaker
Description
A search for the resonant production of a heavy scalar 𝑋 decaying into a Higgs boson and a new lighter scalar 𝑆, through the process 𝑋 → 𝑆(𝑏𝑏)𝐻(𝛾𝛾), where the two photons are consistent with the Higgs boson decay, is performed. The search is conducted combining an integrated luminosity of 140 fb−1 of proton-proton collision data at a centre-of-mass energy of 13 TeV, and 58.6 fb-1 of proton-proton collision data at a centre-of-mass energy of 13.6 TeV, recorded with the ATLAS detector at the LHC from 2015-2018, and 2022-2023 respectively. Similarly to the previous iteration of this search, it is performed for 170 ≤ 𝑚𝑋 ≤ 1000 GeV and 15 ≤ 𝑚𝑆 ≤ 500 GeV and parameterised neural networks are used to enhance the signal purity and to achieve continuous sensitivity in a domain of the (𝑚𝑋, 𝑚𝑆) plane.
