Constraints on Anomalous Quartic Gauge Couplings via Electroweak Production of $\gamma\gamma jj$ at Future Proton-Proton Colliders

TL;DR

This paper assesses the potential of future proton-proton colliders to constrain anomalous quartic gauge couplings through the analysis of the $pp ightarrow \gamma\gamma jj$ process, employing advanced simulation and analysis techniques.

Contribution

It introduces a comprehensive simulation and multivariate analysis framework to evaluate the sensitivity of HL-LHC and FCC-hh to aQGCs, including unitarity considerations and systematic uncertainties.

Findings

FCC-hh significantly improves sensitivity over HL-LHC

Projected limits surpass current ATLAS constraints

Analysis remains robust under 10% systematic uncertainties

Abstract

The investigation of quartic gauge couplings provides a crucial test of the Standard Model and serves as a potential window into new physics at higher energy scales. Within the framework of Effective Field Theory, deviations from the SM can be parameterized through dimension-8 operators. In this study, we analyze the process $pp \rightarrow \gamma\gamma jj$ at the High-Luminosity Large Hadron Collider (HL-LHC) and the Future Circular Collider in hadron mode (FCC-hh) to probe the sensitivity to anomalous quartic gauge couplings (aQGCs), particularly $f_{T8}/\Lambda^4$ and $f_{T9}/\Lambda^4$. Monte Carlo simulations of signal and relevent backgrouds are performed using MadGraph for event generation, Pythia for parton showering and hadronization, and Delphes for detector simulation. A multivariate analysis based on Boosted Decision Trees is employed to optimize the signal-to-background discrimination, incorporating a comprehensive set of kinematic and reconstructed variables of the final state particles. Additionally, we evaluate unitarity-violating effects associated with dimension-8 operators by imposing energy cutoffs on the di-photon invariant mass. The expected exclusion and discovery significances are computed, accounting for systematic uncertainties to ensure a realistic assessment of collider reach. Our findings indicate that the FCC-hh offers significantly improved sensitivity compared to the HL-LHC and current experimental results by ATLAS, reinforcing its potential for probing aQGCs. Notably, even under a 10\% systematic uncertainty, our projected limits for FCC-hh at 95\% confidence level surpass the current best constraints reported by the ATLAS collaboration, highlighting the enhanced discovery prospects at future high-energy colliders.