Probing Neutral Triple Gauge Couplings with Z^* Γ (νν̅γ) Production at Hadron Colliders

We study probes of neutral triple gauge couplings (nTGCs) via Z^*γproduction followed by off-shell decays Z^*→νν̅ at the LHC andfuture pp colliders, including both CP-conserving (CPC) and CP-violating(CPV) couplings. We present the dimension-8 SMEFT operators contributing tonTGCs and derive the correct form factor formulation for the off-shell verticesZ^*γ V^* (V=Z,γ) by matching them with the dimension-8 SMEFToperators. Our analysis includes new contributions enhanced by the largeoff-shell momentum of Z^*, beyond those of the conventional Zγ V^*vertices with on-shell Zγ. We analyze the sensitivity reaches forprobing the CPC/CPV nTGC form factors and the new physics scales of thedimension-8 nTGC operators at the LHC and future 100TeV pp colliders. Wecompare our new predictions with the existing LHC measurements of CPC nTGCs inthe νν̅γ channel and demonstrate the importance of our newmethod.