Slepton pair production at the LHC in NLO+NLL with resummation-improved parton densities

TL;DR

This paper introduces a method for calculating slepton pair production at the LHC using resummation-improved PDFs, which enhances the accuracy and reliability of theoretical cross section predictions by combining advanced PDFs with NLO+NLL calculations.

Contribution

It presents a novel factorisation approach that incorporates resummation-improved PDFs into NLO+NLL calculations, reducing uncertainties and improving prediction consistency.

Findings

Resummation-improved PDFs partially offset resummation effects in matrix elements.

The method reduces scale uncertainties at NLO+NLL.

Enhanced reliability of slepton production cross section predictions at the LHC.

Abstract

Novel PDFs taking into account resummation-improved matrix elements, albeit only in the fit of a reduced data set, allow for consistent NLO+NLL calculations of slepton pair production at the LHC. We apply a factorisation method to this process that minimises the effect of the data set reduction, avoids the problem of outlier replicas in the NNPDF method for PDF uncertainties and preserves the reduction of the scale uncertainty. For Run II of the LHC, left-handed selectron/smuon, right-handed and maximally mixed stau production, we confirm that the consistent use of threshold-improved PDFs partially compensates the resummation contributions in the matrix elements. Together with the reduction of the scale uncertainty at NLO+NLL, the described method further increases the reliability of slepton pair production cross sections at the LHC.