Measurement of the b jet cross section in events with a Z boson in pp(-) collisions at root s 1. 96 TeV

A measurement of the inclusive bottom jet cross section is presented for events containing a Z boson in p (p) over bar collisions at root s=1.96 TeV using the Collider Detector at Fermilab. Z bosons are identified in their electron and muon decay modes, and b jets with E(T)> 20 GeV and vertical bar eta vertical bar < 1.5 are identified by reconstructing a secondary decay vertex. The measurement is based on an integrated luminosity of about 330 pb(-1). A cross section times branching ratio of sigma(Z+b jets)xB(Z ->center dot(+)center dot(-))=0.93 +/- 0.36 pb is found, where B(Z ->center dot(+)center dot(-)) is the branching ratio of the Z boson or gamma(*) into a single flavor dilepton pair (e or mu) in the mass range between 66 and 116 GeV/c(2). The ratio of b jets to the total number of jets of any flavor in the Z sample, within the same kinematic range as the b jets, is 2.36 +/- 0.92%. Here, the uncertainties are the quadratic sum of statistical and systematic uncertainties. Predictions made with next-to-leading order QCD agree, within experimental and theoretical uncertainties, with these measurements. RI Ruiz, Alberto/E-4473-2011; Robson, Aidan/G-1087-2011; De Cecco, Sandro/B-1016-2012; St.Denis, Richard/C-8997-2012; Prokoshin, Fedor/E-2795-2012; Azzi, Patrizia/H-5404-2012