$Z\gamma$ production at NNLO including anomalous couplings

Understand

In this paper we present a next-to-next-to-leading order (NNLO) QCD calculation of the processes $pp\rightarrow l^+l^-\gamma$ and $pp\rightarrow \nu\bar\nu\gamma$ that we have implemented in MCFM.

• Our calculation includes QCD corrections at NNLO both for the Standard Model (SM) and additionally in the presence of $Z\gamma\gamma$ and $ZZ\gamma$ anomalous couplings.
• We compare our implementation, obtained using the jettiness slicing approach, with a previous SM calculation and find broad agreement.
• Focusing on the sensitivity of our results to the slicing parameter, we show that using our setup we are able to compute NNLO cross sections with numerical uncertainties of about $0.1\%$, which is small compared to residual scale uncertainties of a few percent.