Measurement of the single top cross section

We present recent results from searches for single-top-quark production and single-top polarization studies using 3.2 $fb^{-1}$ of data accumulated with the CDF detector at the Fermilab Tevatron. We select events with one charged lepton, large missing transverse energy, and two or three jets, where at least one jet is identified as a b-quark jet using displaced secondary-vertex information from the CDF silicon detector. We employ a boosted decision tree analysis technique and a neural-network jet-flavor separator to improve separation of signal and background and greatly improve the sensitivity of our search.