NLO electroweak corrections to off-shell top-antitop production with leptonic decays at the LHC

TL;DR

This paper presents the first comprehensive calculation of next-to-leading-order electroweak corrections to off-shell top-antitop production with leptonic decays at the LHC, highlighting their significance in high-energy regions.

Contribution

It provides a complete one-loop electroweak correction calculation including off-shell, non-resonant, and interference effects, and compares it with pole approximations for the first time.

Findings

Electroweak corrections are below 1% for total cross section.

Corrections reach up to 15% in high-transverse-momentum regions.

Pole approximation with on-shell W bosons closely matches the full calculation.

Abstract

For the first time the next-to-leading-order electroweak corrections to the full off-shell production of two top quarks that decay leptonically are presented. This calculation includes all off-shell, non-resonant, and interference effects for the 6-particle phase space. While the electroweak corrections are below one per cent for the integrated cross section, they reach up to 15% in the high-transverse-momentum region of distributions. To support the results of the complete one-loop calculation, we have in addition evaluated the electroweak corrections in two different pole approximations, one requiring two on-shell top quarks and one featuring two on-shell W bosons. While the former deviates by up to 10% from the full calculation for certain distributions, the latter provides a very good description for most observables. The increased centre-of-mass energy of the LHC makes the inclusion of electroweak corrections extremely relevant as they are particularly large in the Sudakov regime where new physics is expected to be probed.