Precision from the diphoton Zh channel at FCC-hh

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 (nu(nu) over bar /l(+)l(-) )gamma gamma final states. We study the sensitivity of this channel to the O-phi q((1)), O-phi q((3)), O-phi u and O-phi d 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-phi q((3)), we demonstrate that binning in the Zh rapidity has the potential to improve the reach on O-phi q((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-phi q((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-phi q((3)), reaching a precision of |delta g(1z)| less than or similar to 2 x 10(-4) on the deviations in the ZWW interactions.

Automated summary

The FCC-hh hadron collider will provide access to clean final states, with the Zh production channel showing sensitivity to various SMEFT operators. While O-phi q((3)) shows the best sensitivity, binning in Zh rapidity can improve sensitivity to O-phi q((1)). Estimated bounds at FCC-hh are significantly better than those at HL-LHC and future lepton colliders.