Abstract.
Cross-sections in perturbative QCD generically contain logarithms that grow large in the so-called threshold limit, when emitted gluons are soft. This can potentially make predictions unreliable. Threshold resummation deals with this by including these logarithms to all orders in the strong coupling, which can stabilize the predictions. This has been studied extensively, e.g. reaching next-to-next-to-next-to-leading logarithmic (N3LL) accuracy for the Drell-Yan process, in what is called leading-power (LP) resummation. Recently, more focus has been put on resumming also those logarithms that are suppressed by one order in the soft gluon momentum, which may also give an appreciable contribution. These are referred to as next-to-leading-power (NLP) logarithms.
In this talk I will outline how NLP logarithms arise in perturbative QCD, and how they are resummed in the Drell-Yan process. To this order there are logarithmic contributions both from quark-antiquark and quark-gluon scattering, which must be handled separately. I will then apply the results to the pair-production of sleptons (the supersymmetric scalar counterparts to leptons), which are produced similarly. I will discuss how their production cross-section is impacted by the inclusion of these effects, both by a shift in the cross-section prediction and by lowering the dependence upon the unphysical renormalization scale.
(The slides will be available here)