Measurement of WγW\gamma and ZγZ\gamma Production in ppˉp\bar{p} Collisions at s\sqrt{s} = 1.96 TeV

The Standard Model predictions for $W\gamma$ and $Z\gamma$ production are tested using an integrated luminosity of 200 pb$^{-1}$ of \ppbar collision data collected at the Collider Detector at Fermilab. The cross sections are measured selecting leptonic decays of the $W$ and $Z$ bosons, and photons with transverse energy $E_T>7$ GeV that are well separated from leptons. The production cross sections and kinematic distributions for the $W\gamma$ and $Z\gamma$ are compared to SM predictions.Comment: 7 pages, 4 figures, submitted to PR

Measurement of the ttbar Production Cross Section in ppbar Collisions at sqrt{s}=1.96 TeV using Lepton + Jets Events with Secondary Vertex b-tagging

We present a measurement of the ttbar production cross section using events with one charged lepton and jets from ppbar collisions at a center-of-mass energy of 1.96 TeV. In these events, heavy flavor quarks from top quark decay are identified with a secondary vertex tagging algorithm. From 162 pb-1 of data collected by the Collider Detector at Fermilab, a total of 48 candidate events are selected, where 13.5 +- 1.8 events are expected from background contributions. We measure a ttbar production cross section of 5.6^{+1.2}_{-1.1} (stat.) ^{+0.9}_{0.6} (syst.) pb.Comment: 28 pages, 20 figures. Published in Physical Review

Search for electroweak single top quark production in ppbar collisions at sqrt{s}=1.96 TeV

We report on a search for Standard Model t-channel and s-channel single top quark production in ppbar collisions at a center of mass energy of 1.96 TeV. We use a data sample corresponding to 162 pb^{-1} recorded by the upgraded Collider Detector at Fermilab. We find no significant evidence for electroweak top quark production and set upper limits at the 95% confidence level on the production cross section, consistent with the Standard Model: 10.1 pb for the t-channel, 13.6 pb for the s-channel and 17.8 pb for the combined cross section of t- and s-channel.Comment: 7 pages, 2 figures, accepted by Phys. Rev.

Measurement of the t(t)over-bar production cross section in p(p)over-barcollisions at root s=1.96 TeV using kinematic fitting of b-tagged lepton plus jet events

We report a measurement of the t (t) over bar production cross section using the CDF II detector at the Fermilab Tevatron. The data consist of events with an energetic electron or muon, missing transverse energy, and three or more hadronic jets, at least one of which is identified as a b-quark jet by reconstructing a secondary vertex. The background fraction is determined from a fit of the transverse energy of the leading jet. Using 162 +/- 10 pb(-1) of data, the total cross section is found to be 6.0 +/- 1.6(stat.)+/- 1.2(syst.) pb, which is consistent with the standard model prediction

CMS physics technical design report : Addendum on high density QCD with heavy ions

Peer reviewe

Measurement of the mass difference m(D-s(+))-m(D+) at CDF II

We present a measurement of the mass difference m(D-s(+))-m(D+), where both the D-s(+) and D+ are reconstructed in the phipi(+) decay channel. This measurement uses 11.6 pb(-1) of data collected by CDF II using the new displaced-track trigger. The mass difference is found to be m(D-s(+))-m(D+)=99.41+/-0.38(stat)+/-0.21(syst) MeV/c(2)

Performance studies of the CMS strip tracker before installation

Peer reviewe

Energy Resolution Performance of the CMS Electromagnetic Calorimeter

The energy resolution performance of the CMS lead tungstate crystal electromagnetic calorimeter is presented. Measurements were made with an electron beam using a fully equipped supermodule of the calorimeter barrel. Results are given both for electrons incident on the centre of crystals and for electrons distributed uniformly over the calorimeter surface. The electron energy is reconstructed in matrices of 3 times 3 or 5 times 5 crystals centred on the crystal containing the maximum energy. Corrections for variations in the shower containment are applied in the case of uniform incidence. The resolution measured is consistent with the design goals

Search for the flavor-changing neutral current decay D-0 -\u3emu(+)mu(-) in p(p)over-bar collisions at root s=1.96 TeV

We report on a search for the flavor-changing neutral current decay D-0--\u3emu(+)mu(-) in p (p) over bar collisions at roots=1.96 TeV using 65 pb(-1) of data collected by the CDF II experiment at the Fermilab Tevatron Collider. A displaced-track trigger selects long-lived D-0 candidates in the D-0--\u3emu(+)mu(-) search channel, the kinematically similar D-0--\u3epi(+)pi(-) channel used for normalization, the Cabibbo-favored D-0--\u3eK(-)pi(+) channel used to optimize the selection criteria in an unbiased manner, and their charge conjugates. Finding no signal events in the D-0--\u3emu(+)mu(-) search window, we set an upper limit on the branching fraction B(D-0--\u3emu(+)mu(-))less than or equal to2.5x10(-6) (3.3x10(-6)) at the 90% (95%) confidence level