Combination of D0 measurements of the top quark mass

We present a combination of measurements of the top quark mass by the D0 experiment in the $\mathrm{lepton}+\text{jets}$ and dilepton channels. We use all the data collected in Run I (1992–1996) at $\sqrt{s}=1.8\mathrm{TeV}$ and Run II (2001–2011) at $\sqrt{s}=1.96\mathrm{TeV}$ of the Tevatron $p\overline{p}$ collider, corresponding to integrated luminosities of $0.1{\mathrm{fb}}^{-1}$ and $9.7{\mathrm{fb}}^{-1}$, respectively. The combined result is: $m_t=174.95\pm 0.40(\mathrm{stat})\pm 0.64(\mathrm{syst})\mathrm{GeV}=174.95\pm 0.75\mathrm{GeV}$.

Figure 1

Two-dimensional distribution in the top quark masses extracted from the MC event ensembles in the ME and NW analyses. The statistical correlation $\rho$ is obtained from this distribution.

Figure 2

A summary of the top quark mass measurements used in the D0 combination [9, 10, 11, 12, 13, 14, 15], along with the D0 final result, and the top quark pole mass extracted from the D0 cross section measurement [23]. The latter is not used in the combination. The inner red uncertainty bars represent the statistical uncertainties, while the blue bars represent the total uncertainties. For comparison, we also show the preliminary 2014 world average of $m_t$ [20] which includes D0 Run II $\ell {\ell }^{\prime }$ and $\ell +\text{jets}$ measurements that are now superseded. For the top quark pole mass extracted from the D0 cross section measurement, a 1.1 GeV theory uncertainty is included in the systematic uncertainty, and the statistical uncertainty is determined such as its relative contribution to the experimental uncertainty is the same as for the cross-section measurement.