Search for scalar top quarks in the acoplanar charm jets and missing transverse energy final state in $p\bar{p}$ collisions at $\sqrt{s}=1.96$ TeV

TL;DR

This paper reports a search for scalar top quark pairs decaying into charm quarks and neutralinos in proton-antiproton collisions, finding no excess over the standard model and setting new exclusion limits on their masses.

Contribution

It introduces a novel search strategy for scalar top quarks in a specific decay channel using Tevatron data, extending previous exclusion limits.

Findings

No significant excess observed over standard model predictions.

Set new 95% confidence level exclusion limits on scalar top and neutralino masses.

Analyzed 995 pb$^{-1}$ of data with the D0 detector at Fermilab.

Abstract

We present a search for the pair production of scalar top quarks, $\tilde{t}$, using 995 pb$^{-1}$ of data collected in $p\bar{p}$ collisions with the D0 detector at the Fermilab Tevatron Collider at $\sqrt{s} = 1.96$ TeV. Both scalar top quarks are assumed to decay into a charm quark and a neutralino ($\tilde{\chi}^{0}_{1}$), where $\tilde{\chi}^{0}_{1}$ is the lightest supersymmetric particle. This leads to a final state with two acoplanar charm jets and missing transverse energy. We find the yield of such events to be consistent with the standard model expectation, and exclude sets of $\tilde{t}$ and $\tilde{\chi}^{0}_{1} $ masses at the 95% C.L. that substantially extend the domain excluded by previous searches.