Search for the lightest scalar top quark in events with two leptons in p-pbar collisions at sqrt(s) = 1.96 TeV

TL;DR

This paper reports a search for the lightest scalar top quark in proton-antiproton collisions at 1.96 TeV, using data from the D0 detector, and sets new exclusion limits on its mass.

Contribution

It introduces a new search for the scalar top quark decaying into a bottom quark, lepton, and sneutrino, extending the exclusion domain in the mass plane.

Findings

No evidence for scalar top quark production was observed.

The search significantly extends the exclusion limits in the mass parameter space.

The analysis constrains supersymmetric models with light scalar top quarks.

Abstract

Data collected by the D0 detector at a p-pbar center-of-mass energy of 1.96 TeV at the Fermilab Tevatron Collider have been used to search for pair production of the lightest supersymmetric partner of the top quark decaying into $b \ell \tilde{\nu}$. The search is performed in the $\ell\ell' = e\mu$ and $\mu \mu$ final states. No evidence for this process has been found in data samples of approximately 400 pb^-1. The domain in the [$M(\tilde{t}_1),M(\tilde{\nu})$] plane excluded at the 95% C.L. is substantially extended by this search.