Polarised W plus j production at the LHC: a study at NNLO QCD accuracy

We study polarisation of W-bosons produced in association with one jet at the LHC. In particular, we provide all necessary theoretical ingredients for the precise extraction of polarisation fractions. To that end, we present new polarised predictions up to NNLO QCD accuracy employing the narrow-width approximation, in two phase spaces: inclusive and fiducial. We compare results in the fiducial phase space to a full off-shell computation as well as experimental data. Finally, we fit the polarisation fractions using shape templates and show that NNLO corrections significantly improve their determination.

Automated summary

This study investigates the polarisation of W-bosons produced in association with one jet at the LHC. The necessary theoretical elements for accurately extracting polarisation fractions are provided. New polarised predictions up to NNLO QCD accuracy using the narrow-width approximation are presented in inclusive and fiducial phase spaces. Results in the fiducial phase space are compared to a full off-shell computation and experimental data. Finally, the polarisation fractions are fitted using shape templates, demonstrating that NNLO corrections significantly improve their determination.