Threshold resummation for gaugino pair production at hadron colliders

We present a complete analysis of threshold resummation effects on direct light and heavy gaugino pair production at the Tevatron and the LHC. Based on a new perturbative calculation at next-to-leading order of SUSY-QCD, which includes also squark mixing effects, we resum soft gluon radiation in the threshold region at leading and next-to-leading logarithmic accuracy, retaining at the same time the full SUSY-QCD corrections in the finite coefficient function. This allows us to correctly match the resummed to the perturbative cross section. Universal subleading logarithms are resummed in full matrix form. We find that threshold resummation slightly increases and considerably stabilizes the invariant mass spectra and total cross sections with respect to the next-to-leading order calculation. For future reference, we present total cross sections and their theoretical errors in tabular form for several commonly used SUSY benchmark points, gaugino pairs, and hadron collider energies.