文摘
The mass of the top quark is measured using a sample of $\hbox {t}\bar{\mathrm{t}}$ candidate events with at least six jets in the final state. The sample is selected from data collected with the CMS detector in pp collisions at $\sqrt{s}=7$ ?TeV in 2011 and corresponds to an integrated luminosity of 3.54? $\hbox {fb}^{-1}$ . The mass is reconstructed for each event employing a kinematic fit of the jets to a $\hbox {t}\bar{\mathrm{t}}$ hypothesis. The top-quark mass is measured to be $173.49\pm 0.69\,\mathrm{(stat.)}\pm 1.21\,\mathrm{(syst.)}$ ?GeV. A combination with previously published measurements in other decay modes by CMS yields a mass of $173.54\pm 0.33\,\mathrm{(stat.)}\pm 0.96\,\mathrm{(syst.)}$ ?GeV.