Precision from the diphoton Zh channel at FCC-hh

A bstract The future 100 TeV FCC-hh hadron collider will give access to rare but clean final states which are out of reach of the HL-LHC. One such process is the Zh production channel in the v v ¯ / ℓ + ℓ − γγ final states. We study the sensitivity of this channel to the O φq 1 , O φq 3 , O φu , and O φd SMEFT operators, which parametrize deviations of the W and Z couplings to quarks, or, equivalently, anomalous trilinear gauge couplings (aTGC). While our analysis shows that good sensitivity is only achievable for O φq 3 , we demonstrate that binning in the Zh rapidity has the potential to improve the reach on O φq 1 . Our estimated bounds are one order of magnitude better than projections at HL-LHC and is better than global fits at future lepton colliders. The sensitivity to O φq 3 is competitive with other channels that could probe the same operator at FCC-hh. Therefore, combining the different diboson channels sizeably improves the bound on O φq 3 , reaching a precision of | δg 1 z | ≲ × 10 − 4 on the deviations in the ZWW interactions.