Search for the Supersymmetric Partner of the Top-Quark in $p \bar{p}$ Collisions at $\sqrt{s} = 1.8 {\rm TeV}$

TL;DR

This paper searches for the supersymmetric partner of the top quark in proton-antiproton collisions, finding no evidence and setting limits on the decay branching ratio of top quarks into stop and LSP particles.

Contribution

It provides the first experimental limits on top quark decays into stop and LSP in proton-antiproton collisions at 1.8 TeV.

Findings

No excess over Standard Model expectations observed.

Excluded top decay branching ratios above 45% for LSP masses up to 40 GeV/c^2.

Abstract

We report on a search for the supersymmetric partner of the top quark (stop) produced in $t \bar{t}$ events using $110 {\rm pb}^{-1}$ of $p \bar{p}$ collisions at $\sqrt{s} = 1.8 {\rm TeV}$ recorded with the Collider Detector at Fermilab. In the case of a light stop squark, the decay of the top quark into stop plus the lightest supersymmetric particle (LSP) could have a significant branching ratio. The observed events are consistent with Standard Model $t \bar{t}$ production and decay. Hence, we set limits on the branching ratio of the top quark decaying into stop plus LSP, excluding branching ratios above 45% for a LSP mass up to 40 {\rm GeV/c}$^{2}$.