Slepton pair production with aNNLO+NNLL precision

TL;DR

This paper provides a highly precise calculation of slepton pair production at the LHC, incorporating advanced QCD corrections to improve prediction stability and accuracy for experimental analyses.

Contribution

It introduces a combined aNNLO+NNLL calculation for slepton pair production, enhancing precision and reducing theoretical uncertainties compared to previous results.

Findings

Moderate increase in invariant-mass distributions and total cross sections.

Significant reduction in scale dependence, stabilizing predictions.

Weak dependence on other supersymmetric parameters.

Abstract

We present a calculation of slepton pair production at the LHC at next-to-next-to-leading logarithmic (NNLL) accuracy, matched to approximate next-to-next-to-leading order (aNNLO) QCD corrections. We collect the relevant analytical formulae, discuss the matching of logarithmically enhanced and fixed-order results and describe the transformation of parton densities and hadronic cross sections to and from Mellin space. Numerically, we find a moderate increase of invariant-mass distributions and total cross sections with respect to our previous results at next-to-leading logarithmic (NLL) accuracy matched to next-to-leading order (NLO), and more importantly a further significant reduction of the factorisation and renormalisation scale dependence that stabilises our predictions to the permil level. The dependence on other supersymmetric parameters like squark and gluino masses and sbottom mixing that enter only at NLO is found to be weak, i.e.\ less than two percent, as expected.