Measurement of theσ(W+≥1Jet)/σ(W)Cross Section Ratiofromp¯pCollisions at√s=1.8TeV

The ratio of the $W+\ge 1$ jet cross section to the inclusive $W$ cross section is measured using $W^{\pm }\to e^{\pm }\nu$ events from $\overline{p}p$ collisions at $\sqrt{s}=1.8\mathrm{}\mathrm{TeV}$. The data are from $108{\mathrm{pb}}^{-1\mathrm{}}$ of integrated luminosity collected with the Collider Detector at Fermilab. Measurements of the cross section ratio for jet transverse energy thresholds $\left(E_T^{\min }\right)$ ranging from 15 to 95 GeV are compared to theoretical predictions using next-to-leading-order QCD calculations. Data and theory agree well for $E_T^{\min }>25\mathrm{}\mathrm{GeV}$, where the predictions lie within 1 standard deviation of the measured values.