Implementing invariant mass cuts and finite lifetime effects in top-antitop production at threshold

TL;DR

This paper discusses how to incorporate finite top quark lifetime effects and invariant mass cuts into the theoretical calculation of top-antitop production near threshold using effective field theory methods.

Contribution

It introduces a phase-space matching procedure within NRQCD to accurately account for physical phase-space boundaries in top pair production calculations.

Findings

Effective field theory can incorporate invariant mass cuts.

Finite lifetime effects significantly impact the cross section near threshold.

Phase-space matching improves theoretical predictions.

Abstract

The effects of the finite top quark width in the top pair production cross section close to the threshold are discussed in this talk. We introduce a $t\bar{t}$ cross section with a cut on the invariant masses of the top and antitop that can be calculated theoretically with effective field theory (EFT) methods. The matching procedure to implement the physical phase-space boundaries in the NRQCD framework (``phase-space matching'') is briefly outlined.