A New Method to Measure the Ratio of W and Z Cross Sections

We present a new method for the measurement of the ratio, $R$, of cross sections for~$W$ and~$Z$ production in $p\bar{p}$~collisions at the Fermilab Tevatron. The leptonic signals from~$W$ and~$Z$ decays are treated in a strictly parallel fashion, and the~$p_T$ spectrum of the lepton is used to infer their relative rates. A preliminary measurement has been obtained from data collected with the CDF~II detector corresponding to approximately $350$~pb$^{-1}$. Using this value for~$R$ we extract a value for the width of the $W$~boson.