Precise Measurement of the Top-Quark Mass from $\mathrm{\text{lepton}}+\mathrm{\text{jets}}$ Events

We measure the mass of the top quark using top-quark pair candidate events in the $\mathrm{\text{lepton}}+\mathrm{\text{jets}}$ channel from data corresponding to $1{\mathrm{fb}}^{-1}$ of integrated luminosity collected by the D0 experiment at the Fermilab Tevatron collider. We use a likelihood technique that reduces the jet energy scale uncertainty by combining an in situ jet energy calibration with the independent constraint on the jet energy scale (JES) from the calibration derived using $\mathrm{\text{photon}}+\mathrm{\text{jets}}$ and dijet samples. We find the mass of the top quark to be $171.5\pm 1.8(\mathrm{stat}.+\mathrm{JES})\pm 1.1(\mathrm{syst}.)\mathrm{GeV}$.

Figure 1

Comparison between data and MC 2-jet ($m_{2j}$) and 3-jet ($m_{3j}$) invariant mass distributions.

Figure 2

Mean values of $m_t$ and $k_{\mathrm{jes}}$ from ensemble tests versus true values parameterized by straight lines. Dashed lines represent identical fitted and true values.

Figure 3

(a) Projection of data likelihood onto the $m_t$ axis with best estimate shown. (b) Expected uncertainty distribution for $m_t$ with measured uncertainty indicated by the arrow.