This article presents measurements of tt¯ differential cross-sections in a fiducial phase-space region, using an integrated luminosity of 3.2 fb^{- 1} of proton–proton data at a centre-of-mass energy of s=13 TeV recorded by the ATLAS experiment at the LHC in 2015. Differential cross-sections are measured as a function of the transverse momentum and absolute rapidity of the top quark, and of the transverse momentum, absolute rapidity and invariant mass of the tt¯ system. The tt¯ events are selected by requiring one electron and one muon of opposite electric charge, and at least two jets, one of which must be tagged as containing a b-hadron. The measured differential cross-sections are compared to predictions of next-to-leading order generators matched to parton showers and the measurements are found to be consistent with all models within the experimental uncertainties with the exception of the Powheg-Box+ Herwig++ predictions, which differ significantly from the data in both the transverse momentum of the top quark and the mass of the tt¯ system. © 2017, CERN for the benefit of the ATLAS collaboration.

Title

The European Physical Journal C

Publisher

Springer New York LLC

Publisher Country

United States of America

Indexing

Thomson Reuters

Impact Factor

14.691

Publication Type

Prtinted only

Volume

77

Year

2017

Pages

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