Z polarization in $\gamma\gamma$,gluon-gluon $\to t\bar t Z$ for testing the top quark mass structure and the presence of final interactions

TL;DR

This paper investigates how the production rate of longitudinal Z bosons in gamma-gamma and gluon-gluon collisions leading to top-antitop-Z final states can reveal information about the top quark mass structure and potential final state interactions, including dark matter effects.

Contribution

It introduces a framework to analyze effects of an effective scale-dependent top mass and final state interactions on Z_L production in top pair production processes.

Findings

Potential signatures of scale-dependent top mass in Z_L production rates

Effects of final state interactions, such as dark matter, on top quark processes

Guidelines for experimental tests of top quark mass structure

Abstract

We show what type of effects on the rate of $Z_L$ production in the $\gamma\gamma\to t\bar t Z$ and $gluon~gluon\to t\bar t Z$ processes could be produced by an effective scale dependent top mass or by final state interactions between massive particles for example generated by the presence of dark matter.