The top quark is the heaviest known elementary particle, with a mass about 40 times larger than the mass of its isospin partner, the bottom quark. It decays almost 100% of the time to a $W$ boson and a bottom quark. Using top-antitop pairs at the Tevatron proton-antiproton collider, the CDF and D0 Collaborations have measured the top quark’s mass in different final states for integrated luminosities of up to $5.8{\mathrm{fb}}^{-1}$. This paper reports on a combination of these measurements that results in a more precise value of the mass than any individual decay channel can provide. It describes the treatment of the systematic uncertainties and their correlations. The mass value determined is $173.18\pm 0.56(\mathrm{stat})\pm 0.75(\mathrm{syst})\mathrm{GeV}$ or $173.18\pm 0.94\mathrm{GeV}$, which has a precision of $\pm 0.54\%$, making this the most precise determination of the top-quark mass.

• Received 4 July 2012

DOI:https://doi.org/10.1103/PhysRevD.86.092003