Resonance- and Width-aware Parton Shower Evolution and NLO Matching

Abstract

We introduce a technique for the next-to-leading order accurate simulation of $e^{+}{e}^{-}\to W^{+}{W}^{-}b\bar{b}$ that respects the resonant nature of the process above and near the top-quark pair production threshold. The parton-shower evolution, infrared subtraction and NLO matching account in particular for finite width effects beyond the Breit-Wigner structure considered in resonance-aware approaches. We present first phenomenological results relevant to a potential future electron-positron collider and provide a publicly available simulator based on the ALARIC parton shower and the SHERPA event generator.

Comments: 12 pages, 4 figures