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arXiv · hep-ex/0605118

Top Quark Mass Measurement from Dilepton Events at CDF II with the Matrix-Element Method

Abstract

We describe a measurement of the top quark mass using events with two charged leptons collected by the CDF II detector from $p\bar{p}$ collisions with $\sqrt s = 1.96$ TeV at the Fermilab Tevatron. The likelihood in top mass is calculated for each event by convoluting the leading order matrix element describing $q\bar{q} \to t\bar{t} \to b\ellν_{\ell}\bar{b}\ell'ν_{\ell'}$ with detector resolution functions. The presence of background events in the data sample is modeled using similar calculations involving the matrix elements for major background processes. In a data sample with integrated luminosity of 340 pb$^{-1}$, we observe 33 candidate events and measure $M_{top} = 165.2 \pm 6.1(\textrm{stat.}) \pm 3.4(\textrm{syst.}) \mathrm{~GeV}/c^2.$ This measurement represents the first application of this method to events with two charged leptons and is the most precise single measurement of the top quark mass in this channel.

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BibTeXRIS

A. Abulencia. 2006-07-03. Top Quark Mass Measurement from Dilepton Events at CDF II with the Matrix-Element Method. https://doi.org/10.1103/physrevd.74.032009

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