Search for $WZ$ in the $\ell \nu b\overline{b}$ Final State at CDF

An important search channel for the Higgs boson is associated $WH$ production with subsequent decays of $W \rightarrow \ell \nu$ and $H \rightarrow b\overline{b}$. The resulting final state is shared with standard model $WZ$ production which necessarily must be well-understood. We discuss an important cross-check of the $WH$ search which is to apply the same techniques to measuring the $WZ$ contribution to our event candidate sample. The identification of $b$-quark jets is an important component of searches for a Higgs boson with a mass below 130~GeV/$c^2$. We present results from an improved, artificial neural network $b$-quark jet identification algorithm. Two important quantities associated with the algorithm require calibration from data: the efficiency for identifying a b-quark jet and the corresponding rate of misidentification. These quantities are measured using a data sample heavily enriched in jets from semileptonic $B$ hadron decays. The transverse momentum of the lepton relative to the jet is used to discriminate between $b$-quark jets and lighter quark jets.