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arXiv · 0706.0282

Single Top Results from CDF

Bernd Stelzer
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Abstract

The CDF Collaboration has analyzed 955/pb of CDF II data to search for electroweak single top quark production at the Tevatron. We employ three different analysis techniques to search for a single top signal: multivariate likelihood functions; neural networks; the matrix element analysis technique. The sensitivities to a single top signal at the rate predicted by the Standard Model are 2.1 - 2.6 sigma. The first two analyses observe a deficit of single top-like events and set upper limits on the production cross section. The matrix element analysis observes a 2.3 sigma single top excess and measures a combined t-channel and s-channel cross section of 2.7 +1.5-1.3 pb. Using the same dataset, we have searched for non-Standard Model production of single top quarks through a heavy W' boson resonance. No evidence for a signal is observed. We exclude at the 95 % C.L. W' boson production with masses of 760 GeV/c^2 (790 GeV/c^2) in case the right handed neutrino is smaller (larger) than the mass of the W' boson.

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Bernd Stelzer. 2007-06-02. Single Top Results from CDF. https://arxiv.org/abs/0706.0282

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