Measurement of the top-quark mass in all-jets $$\hbox {t}\bar{\mathrm{t}}$$ t t ¯ events in pp collisions at $$\sqrt{s}=7$$ s = 7 TeV

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.