Abstract: The Collider Detector at Fermilab collected a unique sample of jets originating from bottom-quark fragmentation (b-jets) by selecting online proton-antiproton (p¯p) collisions with a vertex displaced from the p¯p interaction point, consistent with the decay of a bottom-quark hadron. This data set, collected at a center-of-mass energy of 1.96 TeV, and corresponding to an integrated luminosity of 5.4??fb?1, is used to measure the Z-boson production cross section times branching ratio into b¯b. The number of Z?b¯b events is determined by fitting the dijet-mass distribution, while constraining the dominant b-jet background, originating from QCD multijet events, with data. The result, ?(p¯p?Z)×B(Z?b¯b)=1.11±0.08(stat)±0.14(syst)??nb, is the most precise measurement of this process, and is consistent with the standard-model prediction. The data set is also used to search for Higgs-boson production. No significant signal is expected in our data and the first upper limit on the cross section for the inclusive p¯p?H?b¯b process at ?s=1.96??TeV is set, corresponding to 33 times the expected standard-model cross section, or ?=40.6??pb, at the 95% confidence level.
