DØ Note 5397-CONF An Improved Search for Single Top Quarks using Bayesian Neural Networks
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چکیده
We report the results of an improved Bayesian neural network (BNN) analysis of 0.9 fb−1 of DØ data. The observed excess of events over background has a p-value of 0.081%, assuming the background-only hypothesis, which corresponds to a significance of 3.1 standard deviations for a Gaussian density. The p-value computed using the Standard Model (SM) single top production cross section of 2.9 pb is 1.6%, corresponding to an expected significance of 2.2 standard deviations. Assuming the observed excess is due to single top production, we measure a single top quark production cross section of σ(pp̄ → tb+X, tqb+X) = 4.4 −1.4 pb.
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