Scalar Top Quark as the Next-to-Lightest Supersymmetric Particle

TL;DR

This paper investigates the phenomenology of a light scalar top quark as the next-to-lightest supersymmetric particle, focusing on its decay signatures and how to distinguish it from top quark pair production at hadron colliders.

Contribution

It demonstrates methods to differentiate scalar top quark events from top quark pairs and explores how W^+ polarization reveals mixing parameters.

Findings

Scalar top quark can be distinguished from top pairs at colliders.

W^+ polarization provides insights into supersymmetric mixing.

Decays to gravitino are phenomenologically viable.

Abstract

We study phenomenologically the scenario in which the scalar top quark is lighter than any other standard supersymmetric partner and also lighter than the top quark, so that it decays to the gravitino via stop -> W^+ b G. In this case, scalar top quark events would seem to be very difficult to separate from top quark pair production. However, we show that, even at a hadron collider, it is possible to distinguish these two reactions. We show also that the longitudinal polarization of the final $W^+$ gives insight into the scalar top and wino/Higgsino mixing parameters.