Top-Quark Mass Measurement from Dilepton Events at CDF II

Authors

A. Abulencia, University of Illinois, Urbana
Kenneth A. Bloom, University of Nebraska-LincolnFollow
CDF Collaboration

Date of this Version

4-21-2006

Comments

Published by American Physical Society. Phys. Rev. Lett/ 96, 152002 (2006). http://prl.aps.org. Copyright © 2006 American Physical Society. Permission to use.

Abstract

We report a measurement of the top-quark mass using events collected by the CDF II detector from pp̅ collisions at √s = 1.96 TeV at the Fermilab Tevatron. We calculate a likelihood function for the top-quark mass in events that are consistent with tt̅ → b̅ℓ^-ν̅_ℓbℓ′⁺ν_{′ℓ decays. The likelihood is formed as the convolution of the leading-order matrix element and detector resolution functions. The joint likelihood is the product of likelihoods for each of 33 events collected in 340 pb^-1 of integrated luminosity, yielding a top-quark mass Mt = 165.2 ± 6.1(stat) ± 3.4(syst) GeV/c². This first application of a matrix-element technique to tt̅ → bℓ⁺νℓb̅ℓ′^-ν̅ℓ′ decays gives the most precise single measurement of Mt in dilepton events. Combined with other CDF run II measurements using dilepton events, we measure Mt = 167.9 ± 5.2(stat) ± 3.7(syst) GeV/c².}