2026/07/28 by A. Yilmaz, A. Senol, H. Denizli +2
#hep-ph
In this study, the sensitivity to anomalous quartic gauge couplings (aQGCs) is projected via pp → ZZγ production in the 100 TeV proton-proton Future Circular Collider - hadron-hadron (FCC-hh) for an integrated luminosity of 30 ab-1. The ℓℓννγ final state under consideration consists of a same-flavor, opposite-sign lepton pair (electrons or muons) from one Z boson, the invisible decay of the other Z boson into neutrinos, and an accompanying photon. The FCC-hh detector response and its effects on the reconstructed objects are included through a realistic detector simulation. Three multivariate techniques are employed to separate the signal from the relevant SM backgrounds. Unitarity is preserved by a strict, operator-dependent bound on the total transverse mass (MTtot) of the system. The median expected significances are calculated within the Asimov approximation for one anomalous coupling varied at a time and for background systematic uncertainties between 0% and 10%. The highest separation power is obtained with the deep neural network method. The resulting 95% confidence level limits on |fT0/Λ4|, |fT8/Λ4|, |fT9/Λ4| and |fM2/Λ4| in the combined e+μ channel without systematic uncertainties are 2.83× 10-3, 1.65× 10-3, 3.81× 10-3 and 8.97× 10-3 TeV-4, respectively. We have an order of magnitude improvement when compared to current LHC limits with the assumption of 5% systematic uncertainty.