Electroweak Sudakov Corrections to New Physics Searches at the CERN LHC

TL;DR

This paper calculates electroweak Sudakov corrections for Z plus jets production at the LHC, revealing significant negative effects that impact new physics searches at high energies.

Contribution

It introduces a method to compute electroweak Sudakov corrections at NLL accuracy for multiparton processes in a realistic event generator.

Findings

Corrections can reach -40% at 14 TeV.

Real radiation partially cancels virtual corrections.

Results are relevant for ATLAS and CMS analyses.

Abstract

We compute the one-loop electroweak Sudakov corrections to the production process Z (nu bar{nu}) + n jets, with n = 1,2,3, in p p collisions at the LHC. It represents the main irreducible background to new physics searches at the energy frontier. The results are obtained at the leading and next-to-leading logarithmic accuracy by implementing the general algorithm of Denner-Pozzorini in the event generator for multiparton processes ALPGEN. For the standard selection cuts used by ATLAS and CMS collaborations, we show that the Sudakov corrections to the relevant observables can grow up to - 40% at sqrt{s} = 14 TeV. We also include the contribution due to undetected real radiation of massive gauge bosons, to show to what extent the partial cancellation with the large negative virtual corrections takes place in realistic event selections.