A direct measurement of W boson decay width

Based on 85 pb$^{-1}$ data of \ppbar collisions at $\sqrt{s}=1.8$ \tev\ collected using the D{\O}detector at Fermilab during the 1994-1995 run of the Tevatron, we present a direct measurement of the total decay width of the \wb\ boson, $\Gamma_W$. The width is determined from the transverse mass spectrum in the $W \to e+\nu_e$ decay channel and found to be $\Gamma_W = 2.23^{+ 0.15}_{- 0.14}$(stat.)$\pm 0.10$(syst.)GeV, consistent with the expectation from the standard model.