Fully-differential top-pair production at a lepton collider: from threshold to continuum

Fabian Bach, Bijan Chokoufe Nejad, Andre H. Hoang, Wolfgang Kilian, Juergen Reuter, Maximilian Stahlhofen, Thomas Teubner, Christian Weiss

We present an approach to predict exclusive W(+)bW(-)(b) over bar production at lepton colliders that correctly describes the top-anti-top threshold as well as the continuum region. We incorporate t (t) over bar form factors for the NLL threshold resummation derived in NRQCD into a factorized relativistic cross section using an extended double-pole approximation, which accounts for fixed-order QCD corrections to the top decays at NLO. This is combined with the full fixed-order QCD result at NLO for W(+)bW(-)(b) over bar production to obtain predictions that are not only valid at threshold but smoothly transition to the continuum region. Our implementation is based on the Monte Carlo event generator WHIZARD and the code TOPPIK and allows to compute fully-differential threshold-resummed cross sections including the interference with non-resonant background processes. For the first time it is now possible to systematically study general differential observables at future lepton colliders involving the decay products of the top quarks at energies close to the pair production threshold and beyond.

Particle Physics, Research Platform Erwin Schrödinger International Institute for Mathematics and Physics
External organisation(s)
Deutsches Elektronen-Synchrotron DESY, Johannes Gutenberg-Universität Mainz, The University of Liverpool, European Commiss, Eurostat, Universität Siegen
Journal of High Energy Physics
No. of pages
Publication date
Peer reviewed
Austrian Fields of Science 2012
103012 High energy physics
Portal url