The top-antitop threshold at the ILC: NNLL QCD uncertainties

Author(s)
André H. Hoang, Maximilian Stahlhofen
Abstract

We discuss the top-antitop production cross section near threshold at a future linear collider accounting for the NNLL QCD corrections to the anomalous dimension of the leading S-wave production current computed recently within renormalization-group-improved NRQCD perturbation theory. We argue that the still unknown soft NNLL mixing corrections are negligible so that the NNLL QCD corrections to the total cross section can be considered complete for practical purposes. Based on combined variations of the renormalization and matching scales and the overall size of the perturbative corrections we estimate that the NNLL QCD total cross section has a normalization uncertainty of dσ/σ = 5 % at threshold. We present results for the total cross section and also for the experimentally more relevant case, when moderate cuts are imposed on the reconstructed top and antitop invariant masses.

Organisation(s)
Particle Physics
External organisation(s)
Deutsches Elektronen-Synchrotron DESY
Journal
Journal of High Energy Physics
Volume
2014
No. of pages
22
ISSN
1029-8479
Publication date
05-2014
Peer reviewed
Yes
Austrian Fields of Science 2012
103034 Particle physics
Portal url
https://ucris.univie.ac.at/portal/en/publications/the-topantitop-threshold-at-the-ilc-nnll-qcd-uncertainties(bddd7945-d854-4e88-8d15-887ff6b5ae80).html