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arXiv · 0712.3273

First Measurement of the Fraction of Top Quark Pair Production Through Gluon-Gluon Fusion

CDF Collaboration·T. Aaltonen
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Abstract

We present the first measurement of the fraction of top quark pair production through gluon-gluon fusion. We use 0.96/fb of s**(1/2)=1.96 TeV p-pbar collision data recorded with the CDF II detector at Fermilab. We identify the candidate t-tbar events with a high-energy charged lepton, a neutrino candidate, and four or more jets. Using charged particles with low transverse momentum in t-tbar events, we find the fraction of top quark pair production through gluon-gluon fusion to be 0.07+/-0.14(stat)+/-0.07(syst), corresponding to a 95% confidence level upper limit of 0.33, in agreement with the standard model NLO prediction of 0.15+/-0.05.

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CDF Collaboration, T. Aaltonen. 2008-04-08. First Measurement of the Fraction of Top Quark Pair Production Through Gluon-Gluon Fusion. https://doi.org/10.1103/physrevd.78.111101

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