Search for single top quark production in ppbar collisions at sqrt(s)=1.96 TeV

TL;DR

This paper searches for single top quark production at the Fermilab Tevatron using neural networks, setting upper limits on production cross sections due to no observed signal.

Contribution

First application of neural networks to distinguish single top signals from background in Tevatron data.

Findings

No evidence for single top production was found.

Upper limits on cross sections are 6.4 pb (s-channel) and 5.0 pb (t-channel).

Neural networks effectively separate signal from background.

Abstract

We present a search for electroweak production of single top quarks in the s-channel and t-channel using neural networks for signal-background separation. We have analyzed 230 pb$^{-1}$ of data collected with the D0 detector at the Fermilab Tevatron Collider at a center-of-mass energy of 1.96 TeV and find no evidence for a single top quark signal. The resulting 95% confidence level upper limits on the single top quark production cross sections are 6.4 pb in the s-channel and 5.0 pb in the t-channel.