Incorporating all recent theoretical advances, we resum soft-gluon corrections to the total t (t) over bar cross-section at hadron colliders at the next-to-next-to-leading logarithmic (NNLL) order. We perform the resummation in the well established framework of Mellin N-space resummation. We exhaustively study the sources of systematic uncertainty like renormalization and factorization scale variation, power suppressed effects and missing two- and higher-loop corrections. The inclusion of soft-gluon resummation at NNLL brings only a minor decrease in the perturbative uncertainty with respect to the NLL approximation, and a small shift in the central value, consistent with the quoted uncertainties. These numerical predictions agree with the currently available measurements from the Tevatron and LHC and have uncertainty of similar size. We conclude that significant improvements in the t (t) over bar cross-sections can potentially be expected only upon inclusion of the complete NNLO corrections. (C) 2012 Elsevier B.V. All rights reserved
Cacciari, M., Czakon, M., Mangano, M., Mitov, A., Nason, P. (2012). Top-pair production at hadron colliders with next-to-next-to-leading logarithmic soft-gluon resummation. PHYSICS LETTERS. SECTION B, 710(4-5), 612-622 [10.1016/j.physletb.2012.03.013].
Top-pair production at hadron colliders with next-to-next-to-leading logarithmic soft-gluon resummation
Nason, Paolo
2012
Abstract
Incorporating all recent theoretical advances, we resum soft-gluon corrections to the total t (t) over bar cross-section at hadron colliders at the next-to-next-to-leading logarithmic (NNLL) order. We perform the resummation in the well established framework of Mellin N-space resummation. We exhaustively study the sources of systematic uncertainty like renormalization and factorization scale variation, power suppressed effects and missing two- and higher-loop corrections. The inclusion of soft-gluon resummation at NNLL brings only a minor decrease in the perturbative uncertainty with respect to the NLL approximation, and a small shift in the central value, consistent with the quoted uncertainties. These numerical predictions agree with the currently available measurements from the Tevatron and LHC and have uncertainty of similar size. We conclude that significant improvements in the t (t) over bar cross-sections can potentially be expected only upon inclusion of the complete NNLO corrections. (C) 2012 Elsevier B.V. All rights reservedI documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.