Drell-Yan lepton pair production at NNLO QCD with parton showers

We present a simple approach to combine NNLO QCD calculations and parton showers, based on the unlops technique. We apply the method to the computation of Drell-Yan lepton-pair production at the Large Hadron Collider. We comment on possible improvements and intrinsic uncertainties.

Figure 1

Comparison between fewz and sherpa for rapidity and invariant mass spectra of the Drell-Yan lepton pair. The gray solid (blue hatched) band shows scale uncertainties associated with the NNLO (NLO) prediction, obtained by varying ${\mu }_{R/F}$ in the range $m_{ll}/2\le \mu \le 2m_{ll}$.

Figure 2

Transverse momentum and rapidity spectrum of the electron. The gray solid (blue hatched) band shows scale uncertainties obtained by varying ${\mu }_{R/F/Q}$ (${\mu }_Q$) in the range $m_{ll}/2\le \mu \le 2m_{ll}$.

Figure 3

${\mathrm{UN}}^2\mathrm{LOPS}$ prediction for the transverse momentum spectrum of the Drell-Yan lepton pair in comparison to ATLAS data from [43] (left panel) and CMS data from [42] (right panel). The gray solid (blue hatched) band shows scale uncertainties obtained by varying ${\mu }_{R/F/Q}$ (${\mu }_Q$) in the range $m_{ll}/2\le \mu \le 2m_{ll}$.