Measurement of the top quark mass in the dilepton channel

Abstract

We report a measurement of the top quark mass using six candidate events for the process pp̅→tt̅+X^→l⁺νbl^-ν̅b+X, observed in the DØ experiment at the Fermilab pp̅ collider. Using maximum likelihood fits to the dynamics of the decays, we measure a mass for the top quark of m_t=168.4±12.3(stat)±3.6(syst) Gev. We combine this result with our previous measurement in the tt̅→l+jets channel to obtain m_t=172.1±7.1 GeV as the best value of the mass of the top quark measured by DØ.