Mu3e

Abstract:

We present a measurement of the top quark pair production cross section in pp̄ collisions at s=1.96TeV using 318pb-1 of data collected with the Collider Detector at Fermilab. We select tt̄ decays into the final states eν+jets and μν+jets, in which at least one b quark from the t-quark decays is identified using a secondary vertex-finding algorithm. Assuming a top quark mass of 178GeV/c2, we measure a cross section of 8.7±0.9(stat)-0. 9+1.1(syst)pb. We also report the first observation of tt̄ with significance greater than 5σ in the subsample in which both b quarks are identified, corresponding to a cross section of 10.1-1.4+1.6(stat)-1.3+2.0(syst) pb. © 2006 The American Physical Society.

Abstract:

We present the results of a search for standard model Higgs boson production with decay to WW*, identified through the leptonic final states e+e-ν̄ν,e±μ.

Abstract:

A measurement of the inclusive bottom jet cross section is presented for events containing a Z boson in pp̄ collisions at s=1.96TeV using the Collider Detector at Fermilab. Z bosons are identified in their electron and muon decay modes, and b jets with ET>20GeV and |η|<1.5 are identified by reconstructing a secondary decay vertex. The measurement is based on an integrated luminosity of about 330pb-1. A cross section times branching ratio of σ(Z+bjets)×B(Z→ℓ+ℓ-)=0.93±0.36pb is found, where B(Z→ℓ+ℓ-) is the branching ratio of the Z boson or γ* into a single flavor dilepton pair (e or μ) in the mass range between 66 and 116GeV/c2. 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. © 2006 The American Physical Society.