One-loop QCD interconnection effects in pair production of top quarks

TL;DR

This paper calculates one-loop QCD corrections that connect production and decay stages of top quark pairs, affecting invariant mass distributions but resulting in a small mass shift below 100 MeV.

Contribution

It provides the first detailed calculation of non-factorizable QCD corrections to off-shell top-pair production and decay at various colliders.

Findings

Non-factorizable corrections can be large.

Mass shift due to corrections is below 100 MeV.

Invariant mass distributions are significantly affected.

Abstract

We calculate the one-loop non-factorizable QCD corrections to the production and decay of pairs of top quarks at various collider experiments. These non-factorizable corrections interconnect the different production and decay stages of the off-shell top-pair production processes. This in particular affects the invariant-mass distributions of the off-shell top quarks, resulting in a shift of the maximum of the distorted Breit-Wigner distributions. Although the non-factorizable corrections can be large, the actual shift in the mass as determined from the peak position of the corrected Breit-Wigner line-shape is below $100\MeV$.