Direct Measurement of theWBoson Width

We present a direct measurement of the width of the $W$ boson using the shape of the transverse mass distribution of $W\ensuremath{\rightarrow}e\ensuremath{\nu}$ candidate events. Data from approximately $1\text{ }\text{ }{\mathrm{fb}}^{\ensuremath{-}1}$ of integrated luminosity recorded at $\sqrt{s}=1.96\text{ }\text{ }\mathrm{TeV}$ by the D0 detector at the Fermilab Tevatron $p\overline{p}$ collider are analyzed. We use the same methods and data sample that were used for our recently published $W$ boson mass measurement, except for the modeling of the recoil, which is done with a new method based on a recoil library. Our result, $2.028\ifmmode\pm\else\textpm\fi{}0.072\text{ }\text{ }\mathrm{GeV}$, is in agreement with the predictions of the standard model.