Search for large extra dimensions in final states containing one photon or jet and large missing transverse energy produced in p anti-p collisions at s**(1/2) = 1.96-TeV

The authors present the results of searches for large extra dimensions in samples of events with large missing transverse energy E{sub T} and either a photon or a jet produced in p{bar p} collisions at {radical}s = 1.96 TeV collected with the CDF II detector. For {gamma} + E{sub T} and jet + E{sub T} candidate samples corresponding to 2.0 fb{sup -1} and 1.1 fb{sup -1} of integrated luminosity respectively, they observe good agreement with standard model expectations and obtain a combined lower limit on the fundamental parameter of the large extra dimensions model, M{sub D}, as a function of the number of extra dimensions in the model

Search for Standard Model Higgs Boson Production in Association with a W Boson at CDF

We present a search for standard model Higgs boson production in association with a W boson in proton-antiproton collisions (p{bar p} {yields} W{sup {+-}}H {yields} {ell}{nu}b{bar b}) at a center of mass energy of 1.96 TeV. The search employs data collected with the CDF II detector which correspond to an integrated luminosity of approximately 1 fb{sup -1}. We select events consistent with a signature of a single lepton (e{sup {+-}}/{mu}{sup {+-}}), missing transverse energy, and two jets. Jets corresponding to bottom quarks are identified with a secondary vertex tagging method and a neural network filter technique. The observed number of events and the dijet mass distributions are consistent with the standard model background expectations, and we set 95% confidence level upper limits on the production cross section times branching ratio ranging from 3.9 to 1.3 pb for Higgs boson masses from 110 to 150 GeV/c{sup 2}, respectively

Exclusion of an Exotic Top Quark with -4/3 Electric Charge Using Soft Lepton Tagging

We present a measurement of the electric charge of the top quark using p{bar p} collisions corresponding to an integrated luminosity of 2.7 fb{sup -1} at the CDF II detector. We reconstruct t{bar t} events in the lepton+jets final state and use kinematic information to determine which b-jet is associated with the leptonically- or hadronically-decaying t-quark. Soft lepton taggers are used to determine the b-jet flavor. Along with the charge of the W boson decay lepton, this information permits the reconstruction of the top quark's electric charge. Out of 45 reconstructed events with 2.4 {+-} 0.8 expected background events, 29 are reconstructed as tt with the standard model +2/3 charge, whereas 16 are reconstructed as t{bar t} with an exotic -4/3 charge. This is consistent with the standard model and excludes the exotic scenario at 95% confidence level. This is the strongest exclusion of the exotic charge scenario and the first to use soft leptons for this purpose

Search for Standard Model Higgs Boson Production in Association with a W Boson using a Neural Network

We present a search for standard model Higgs boson production in association with a W boson in proton-antiproton collisions (p{bar p} {yields} W{sup {+-}}H {yields} {ell}{nu}b{bar b}) at a center of mass energy of 1.96 TeV. The search employs data collected with the CDF II detector that correspond to an integrated luminosity of approximately 1.9 fb{sup -1}. We select events consistent with a signature of a single charged lepton (e{sup {+-}}/{mu}{sup {+-}}), missing transverse energy, and two jets. Jets corresponding to bottom quarks are identified with a secondary vertex tagging method, a jet probability tagging method, and a neural network filter. We use kinematic information in an artificial neural network to improve discrimination between signal and background compared to previous analyses. The observed number of events and the neural network output distributions are consistent with the standard model background expectations, and we set 95% confidence level upper limits on the production cross section times branching fraction ranging from 1.2 to 1.1 pb or 7.5 to 102 times the standard model expectation for Higgs boson masses from 110 to 150 GeV/c{sup 2}, respectively

Top Quark Mass Measurement in the Lepton plus Jets Channel Using a Modified Matrix Element Method

The authors report a measurement of the top quark mass, m{sub t}, obtained from p{bar p} collisions at {radical}s = 1.96 TeV at the Fermilab Tevatron using the CDF II detector. They analyze a sample corresponding to an integrated luminosity of 1.9 rfb{sup -1}. They select events with an electron or muon, large missing transverse energy, and exactly four high-energy jets in the central region of the detector, at least one of which is tagged as coming from a b quark. They calculate a signal likelihood using a matrix element integration method, where the matrix element is modified by using effective propagators to take into account assumptions on event kinematics. The event likelihood is a function of m{sub t} and a parameter JES that determines in situ the calibration of the jet energies. They use a neural network discriminant to distinguish signal from background events. They also apply a cut on the peak value of each event likelihood curve to reduce the contribution of background and badly reconstructed events. Using the 318 events that pass all selection criteria, they find m{sub t} = 172.7 {+-} 1.8 (stat. + JES) {+-} 1.2(syst.) GeV/c{sup 2}

Search for new physics in lepton + photon + X events with 929 pb**(-1) of p anti-p collisions at s**(1/2) = 1.96-TeV

The authors present results of a search at CDF in 929 {+-} 56 pb{sup -1} of p{bar p} collisions at 1.96 TeV for the anomalous production of events containing a high-transverse momentum charged lepton ({ell}, either e or {mu}) and photon ({gamma}), accompanied by missing transverse energy (E{sub T}), and/or additional leptons and photons, and jets (X). They use the same selection criteria as in a previous CDF Run I search, but with an order-magnitude larger data set, a higher p{bar p} collisions energy, and the CDF II detector. They find 163 {ell}{gamma}E{sub T} + X events, compared to an expectation of 150.6 {+-} 13.0 events. They observe 74 {ell}{ell}{gamma} + X events, compared to an expectation of 65.1 {+-} 7.7 events. They find no events similar to the Run II ee{gamma}{gamma}E{sub T} event