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arXiv · 1608.00574

Observing the Top Energy Asymmetry at the LHC

Stefan Berge·Susanne Westhoff
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Abstract

The top-antitop energy asymmetry is a promising observable of the charge asymmetry in jet-associated top-quark pair production at the LHC. We present new predictions of the energy asymmetry in proton-proton collisions at 13 TeV, including QCD corrections at the next-to-leading perturbative order. The effect of QCD corrections on the observable is moderate. With suitable phase-space cuts, the asymmetry can be enhanced at the cost of reducing the cross section. For instance, for a cross section of $1\,\text{pb}$ after cuts, we predict an energy asymmetry of $-6.5^{\,+0.1}_{\,-0.2}\%$ at the next-to-leading order in QCD. We also investigate scale uncertainties and parton-shower effects, which partially cancel in the normalized asymmetry. Our results provide a sound basis for a measurement of the energy asymmetry at the LHC during run II.

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Stefan Berge, Susanne Westhoff. 2016-08-01. Observing the Top Energy Asymmetry at the LHC. https://doi.org/10.1103/physrevd.95.014035

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