195 research outputs found
Search for WW and WZ production in lepton plus jets final state at CDF
We present a search for WW and WZ production in final states that contain a charged lepton (electron or muon) and at least two jets, produced in sqrt(s) = 1.96 TeV ppbar collisions at the Fermilab Tevatron, using data corresponding to 1.2 fb-1 of integrated luminosity collected with the CDF II detector. Diboson production in this decay channel has yet to be observed at hadron colliders due to the large single W plus jets background. An artificial neural network has been developed to increase signal sensitivity, as compared with an event selection based on conventional cuts. We set a 95% confidence level upper limit of sigma_{WW}* BR(W->lnu,W->jets)+ sigma_{WZ}*BR(W->lnu,Z->jets)We present a search for WW and WZ production in final states that contain a charged lepton (electron or muon) and at least two jets, produced in √s=1.96 TeV pp̅ collisions at the Fermilab Tevatron, using data corresponding to 1.2 fb-1 of integrated luminosity collected with the CDF II detector. Diboson production in this decay channel has yet to be observed at hadron colliders due to the large single W plus jets background. An artificial neural network has been developed to increase signal sensitivity, as compared with an event selection based on conventional cuts. We set a 95% confidence level upper limit of σWW×BR(W→ℓνℓ,W→jets)+σWZ×BR(W→ℓνℓ,Z→jets)<2.88 pb, which is consistent with the standard model next-to-leading-order cross section calculation for this decay channel of 2.09±0.12 pb.Peer reviewe
Silicon photonics in Pirelli
Silicon is the dominant material in the microelectronic industry and silicon photonics is rapidly gaining importance as a technological platform for a wide range of applications in telecom, and optical interconnect. It allows the implementation of many photonic functions through the use of wafer-scale technologies normally used for advanced CMOS-processing. In this paper some of the most important issues toward a practical implementation of Silicon photonics into an industrial device will be addressed: low loss waveguides, polarization handling, tunability, hitless switching. A tunable Add-Drop multiplexer has been chosen as a case Study of a fully integrated device
Searching the inclusive l γe T+b-quark signature for radiative top quark decay and non-standard-model processes
We compare the inclusive production of events containing a lepton (á), a photon (γ), significant transverse momentum imbalance (E T), and a jet identified as containing a b-quark, to SM predictions. The search uses data produced in proton-antiproton collisions at s=1.96TeV corresponding to 1.9fb-1 of integrated luminosity taken with the CDF detector. We find 28 áγbET events versus an expectation of 31.0-3.5+4.1 events. If we further require events to contain at least three jets and large total transverse energy, the largest SM source is radiative top-quark pair production, tt̄+γ. In the data we observe 16 tt̄γ candidate events versus an expectation from SM sources of 11.2-2.1+2.3. Assuming the difference between the observed number and the predicted non-top-quark total of 6.8-2.0+2.2 is due to SM top-quark production, we estimate the tt̄γ cross section to be 0.15±0.08pb. © 2009 The American Physical Society
Measurement of resonance parameters of orbitally excited narrow B0 mesons
We report a measurement of resonance parameters of the orbitally excited (L=1) narrow B0 mesons in decays to B(*)+Ï€- using 1.7fb-1 of data collected by the CDF II detector at the Fermilab Tevatron. The mass and width of the B2*0 state are measured to be m(B2*0)=5740.2-1.8+1. 7(stat)-0.8+0.9(syst)MeV/c2 and Î (B2*0)=22.7-3.2+3.8(stat)-10. 2+3.2(syst)MeV/c2. The mass difference between the B2*0 and B10 states is measured to be 14.9-2.5+2.2(stat)-1.4+1.2(syst)MeV/c2, resulting in a B10 mass of 5725.3-2.2+1.6(stat)-1.5+1.4(syst)MeV/c2. This is currently the most precise measurement of the masses of these states and the first measurement of the B2*0 width. © 2009 The American Physical Society
Search for lepton flavor violating decays of a heavy neutral particle in p(p)over-bar collisions at root s=1.8 TeV
We report on a search for a high mass, narrow width particle that decays directly to emu, etau, or mutau. We use approximately 110 pb(-1) of data collected with the Collider Detector at Fermilab from 1992 to 1995. No evidence of lepton flavor violating decays is found. Limits are set on the production and decay of sneutrinos with R-parity violating interactions
Effects of Carbohydrate Counting on Glucose Control and Quality of Life Over 24 Weeks in Adult Patients With Type 1 Diabetes on Continuous Subcutaneous Insulin Infusion: A randomized, prospective clinical trial (GIOCAR)
Measurement of the top quark mass at CDF using the `neutrino phi weighting' template method on a lepton plus isolated track sample
We present a measurement of the top quark mass with t{bar t} dilepton events produced in p{bar p} collisions at the Fermilab Tevatron ({radical}s = 1.96 TeV) and collected by the CDF II detector. A sample of 328 events with a charged electron or muon and an isolated track, corresponding to an integrated luminosity of 2.9 fb{sup -1}, are selected as t{bar t} candidates. To account for the unconstrained event kinematics, we scan over the phase space of the azimuthal angles ({phi}{sub {nu}1}, {phi}{sub {nu}2}) of neutrinos and reconstruct the top quark mass for each {phi}{sub {nu}1}, {phi}{sub {nu}2} pair by minimizing a {chi}{sup 2} function in the t{bar t} dilepton hypothesis. We assign {chi}{sup 2}-dependent weights to the solutions in order to build a preferred mass for each event. Preferred mass distributions (templates) are built from simulated t{bar t} and background events, and parameterized in order to provide continuous probability density functions. A likelihood fit to the mass distribution in data as a weighted sum of signal and background probability density functions gives a top quark mass of 165.5{sub -3.3}{sup +3.4}(stat.){+-}3.1(syst.) GeV/c{sup 2}
Search for new physics in the mu mu+e/mu + is not an element of T channel with a low-pT lepton threshold at the Collider Detector at Fermilab
A search for new physics using three-lepton (trilepton) data collected with the CDF II detector and corresponding to an integrated luminosity of 976 pb(-1) is presented. The standard model predicts a low rate of trilepton events, which makes some supersymmetric processes, such as chargino-neutralino production, measurable in this channel. The mu mu + l signature is investigated, where l is an electron or a muon, with the additional requirement of large missing transverse energy. In this analysis, the lepton transverse momenta with respect to the beam direction (p(T)) are as low as 5 GeV/c, a selection that improves the sensitivity to particles that are light as well as to ones that result in leptonically decaying tau leptons. At the same time, this low-p(T) selection presents additional challenges due to the non-negligible heavy-quark background at low lepton momenta. This background is measured with an innovative technique using experimental data. Several dimuon and trilepton control regions are investigated, and good agreement between experimental results and standard-model predictions is observed. In the signal region, we observe one three-muon event and expect 0.4 +/- 0.1 mu mu + l events from standard-model processes.We thank the Fermilab staff and the technical staffs of the participating institutions for their vital contributions. This work was supported by the U.S. Department of Energy and National Science Foundation; the Italian Istituto Nazionale di Fisica Nucleare; the Ministry of Education, Culture, Sports, Science and Technology of Japan; the Natural Sciences and Engineering Research Council of Canada; the National Science Council of the Republic of China; the Swiss National Science Foundation; the A.P. Sloan Foundation; the Bundesministerium für Bildung und Forschung, Germany; the Korean Science and Engineering Foundation and the Korean Research Foundation; the Science and Technology Facilities Council and the Royal Society, UK; the Institut National de Physique Nucleaire et Physique des Particules/CNRS; the Russian Foundation for Basic Research; the Ministerio de Ciencia e Innovación and Programa Consolider-Ingenio 2010, Spain; the Slovak R&D Agency; and the Academy of Finland.Peer reviewe
The NARCONON™ drug education curriculum for high school students: A non-randomized, controlled prevention trial
<p>Abstract</p> <p>Background</p> <p>An estimated 13 million youths aged 12 to 17 become involved with alcohol, tobacco and other drugs annually. The number of 12- to 17-year olds abusing controlled prescription drugs increased an alarming 212 percent between 1992 and 2003. For many youths, substance abuse precedes academic and health problems including lower grades, higher truancy, drop out decisions, delayed or damaged physical, cognitive, and emotional development, or a variety of other costly consequences. For thirty years the Narconon program has worked with schools and community groups providing single educational modules aimed at supplementing existing classroom-based prevention activities. In 2004, Narconon International developed a multi-module, universal prevention curriculum for high school ages based on drug abuse etiology, program quality management data, prevention theory and best practices. We review the curriculum and its rationale and test its ability to change drug use behavior, perceptions of risk/benefits, and general knowledge.</p> <p>Methods</p> <p>After informed parental consent, approximately 1000 Oklahoma and Hawai'i high school students completed a modified <it>Center for Substance Abuse Prevention (CSAP) Participant Outcome Measures for Discretionary Programs </it>survey at three testing points: baseline, one month later, and six month follow-up. Schools assigned to experimental conditions scheduled the Narconon curriculum between the baseline and one-month follow-up test; schools in control conditions received drug education after the six-month follow-up. Student responses were analyzed controlling for baseline differences using analysis of covariance.</p> <p>Results</p> <p>At six month follow-up, youths who received the Narconon drug education curriculum showed reduced drug use compared with controls across all drug categories tested. The strongest effects were seen in all tobacco products and cigarette frequency followed by marijuana. There were also significant reductions measured for alcohol and amphetamines. The program also produced changes in knowledge, attitudes and perception of risk.</p> <p>Conclusion</p> <p>The eight-module Narconon curriculum has thorough grounding in substance abuse etiology and prevention theory. Incorporating several historically successful prevention strategies this curriculum reduced drug use among youths.</p
Measurement of the inclusive jet cross section using the k(T) algorithm in p(p)over-bar collisions at root s=1.96 TeV
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