Precision Measurement of the Top Quark Mass in $L\mathbf{\text{epton}}+J\mathbf{\text{ets}}$ Final States

We measure the mass of the top quark in $\text{lepton}+\text{jets}$ final states using the full sample of $p\overline{p}$ collision data collected by the D0 experiment in Run II of the Fermilab Tevatron Collider at $\sqrt{s}=1.96\mathrm{TeV}$, corresponding to $9.7{\mathrm{fb}}^{-1}$ of integrated luminosity. We use a matrix element technique that calculates the probabilities for each event to result from $t\overline{t}$ production or background. The overall jet energy scale is constrained in situ by the mass of the $W$ boson. We measure $m_t=174.98\pm 0.76\mathrm{GeV}$. This constitutes the most precise single measurement of the top-quark mass.

Figure 1

(a) Two-dimensional likelihood $\mathcal{L}({\overrightarrow{x}}_1,{\overrightarrow{x}}_2,\dots ,{\overrightarrow{x}}_N;m_t,k_{\mathrm{JES}})/{\mathcal{L}}_{\max }$ for data. Fitted contours of equal probability are overlaid as solid lines. The maximum is marked with a cross. Note that the bin boundaries do not necessarily correspond to the grid points on which $\mathcal{L}$ is calculated. (b) Expected uncertainty distributions for $m_t$ with the measured uncertainty indicated by the arrow.

Figure 2

(a) Invariant mass of the jet pair matched to one of the $W$ bosons. (b) Invariant mass of the $t\overline{t}$ system. In the ratio of data to SM prediction, the total systematic uncertainty is shown as a shaded band.