Download or read book Evidence of W Production in Pp Collisions at S written by and published by . This book was released on 2015 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: Here we report evidence of triple gauge boson production pp→W(l?)??+X, which is accessible for the first time with the 8 TeV LHC data set. The fiducial cross section for this process is measured in a data sample corresponding to an integrated luminosity of 20.3 fb−1, collected by the ATLAS detector in 2012. Events are selected using the W boson decay to e? or ?? as well as requiring two isolated photons. The measured cross section is used to set limits on anomalous quartic gauge couplings in the high diphoton mass region.

Download or read book Evidence for the Production of Two W Bosons with the Same Electric Charge and Two Jets in 20 3 Fb 1 of pp Collisions at sqrt s written by Alexander Sood and published by . This book was released on 2014 with total page 155 pages. Available in PDF, EPUB and Kindle. Book excerpt: This dissertation presents a measurement of \ssWW production in proton-proton collisions with a center-of-mass energy of 8 TeV at the Large Hadron Collider using the ATLAS detector. The $W$ bosons are required to decay leptonically, giving a signature of two leptons of the same electric charge, two jets, and missing transverse energy. The analysis is performed on the entire 8 TeV dataset, corresponding to an integrated luminosity of 20.3 fb$^{-1}$. The cross section is measured in two fiducial regions, and an excess over the background-only prediction is observed with a significance of 4.5$\sigma$ for inclusive \ssWW production and 3.6$\sigma$ for electroweak \ssWW production. The measured cross sections are in agreement with Standard Model predictions, and limits are set on anomalous quartic gauge couplings.

Download or read book Spin Correlations in tt Events from pp Collisions written by Boris Lemmer and published by Springer. This book was released on 2015-06-24 with total page 246 pages. Available in PDF, EPUB and Kindle. Book excerpt: This thesis introduces readers to the Standard Model, the top quark and its properties, before explaining the concept of spin correlation measurement. The first measurement of top quark spin correlations at the LHC in the lepton+jets decay channel is presented. As the heaviest elementary particle, the top quark plays an essential role in the Standard Model of elementary particle physics. In the case of top quarks being produced in pairs at hadron colliders, the Standard Model predicts their spins to be correlated. The degree of correlation depends on both the production mechanism and properties of the top quark. Any deviation from the Standard Model prediction can be an indicator for new physics phenomena. The thesis employs an advanced top quark reconstruction algorithm including dedicated identification of the up- and down-type quarks from the W boson decay.

Download or read book Measurement of Associated W Charm Production in Pp Collisions at sqrt s written by and published by . This book was released on 2014 with total page 63 pages. Available in PDF, EPUB and Kindle. Book excerpt: Measurements are presented of the associated production of a W boson and a charm-quark jet (W + c) in pp collisions at a center-of-mass energy of 7 TeV. The analysis is conducted with a data sample corresponding to a total integrated luminosity of 5 inverse femtobarns, collected by the CMS detector at the LHC. W boson candidates are identified by their decay into a charged lepton (muon or electron) and a neutrino. The W + c measurements are performed for charm-quark jets in the kinematic region $p_T^{jet} \gt$ 25 GeV, $

Download or read book Measurement of W W Production and Search for the Higgs Boson in Pp Collisions at Sqrt s written by and published by . This book was released on 2011 with total page 47 pages. Available in PDF, EPUB and Kindle. Book excerpt: A measurement of WW production in pp collisions at sqrt(s) = 7 TeV and a search for the Higgs boson are reported. The WW candidates are selected in events with two leptons, either electrons or muons. The measurement is performed using LHC data recorded with the CMS detector, corresponding to an integrated luminosity of 36 inverse picobarns. The pp to WW cross section is measured to be 41.1 +/- 15.3 (stat) +/- 5.8 (syst) +/- 4.5 (lumi) pb, consistent with the standard model prediction. Limits on WW gamma and WWZ anomalous triple gauge couplings are set. The search for the standard model Higgs boson in the WW decay mode does not reveal any evidence of excess above backgrounds. Limits are set on the production of the Higgs boson in the context of the standard model and in the presence of a sequential fourth family of fermions with high masses. In the latter context, a Higgs boson with mass between 144 and 207 GeV is ruled out at 95% confidence level.

Download or read book A Measurement of W Boson Pair Production in Pp Collisions at Wurzel s written by Philip Sommer and published by . This book was released on 2016 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book The Charge Asymmetry in W Bosons Production in Pp Collisions at the S written by David Khatidze and published by . This book was released on 2009 with total page 394 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Measurement of the Production Cross Section for a W Boson and Two B Jets in Pp Collisions at sqrt s written by and published by . This book was released on 2014 with total page 22 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Evidence for Exclusive oW W Production and Constraints on Anomalous Quartic Gauge Couplings in Pp Collisions at s written by and published by . This book was released on 2016 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Measurement of W Boson Production in Pp Collisions at 5 02 TeV and Optimisation of Electron Identification in Pb Pb Collisions with the ATLAS Detector written by Jakub Kremer (fizyka) and published by . This book was released on 2019 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book 60 Years Of Cern Experiments And Discoveries written by Herwig Schopper and published by World Scientific. This book was released on 2015-07-13 with total page 452 pages. Available in PDF, EPUB and Kindle. Book excerpt: The book is a compilation of the most important experimental results achieved during the past 60 years at CERN - from the mid-1950s to the latest discovery of the Higgs particle. Covering the results from the early accelerators at CERN to those most recent at the LHC, the contents provide an excellent review of the achievements of this outstanding laboratory. Not only presented is the impressive scientific progress achieved during the past six decades, but also demonstrated is the special way in which successful international collaboration exists at CERN.

Download or read book A Search in the Two photon Final State for Evidence of New Particle Production in Pp Collisions at square Root 8 written by Rachel Paula Yohay and published by . This book was released on 2012 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Search for W to Tb Decays in the Lepton Jets Final State in Pp Collisions at sqrt s written by and published by . This book was released on 2014 with total page 35 pages. Available in PDF, EPUB and Kindle. Book excerpt: Results are presented from a search for the production of a heavy gauge boson W' decaying into a top and a bottom quark, using a data set collected by the CMS experiment at sqrt(s) = 8 TeV and corresponding to an integrated luminosity of 19.5 inverse femtobarns. Various models of W'-boson production are studied by allowing for an arbitrary combination of left- and right-handed couplings. The analysis is based on the detection of events with a lepton (e, mu), jets, and missing transverse energy in the final state. No evidence for W'-boson production is found and 95% confidence level upper limits on the production cross section times branching fraction are obtained. For W' bosons with purely right-handed couplings, and for those with left-handed couplings assuming no interference effects, the observed 95% confidence level limit is M(W')> 2.05 TeV. For W' bosons with purely left-handed couplings, including interference effects, the observed 95% confidence level limit is M(W')> 1.84 TeV. The results presented in this paper are the most stringent limits published to date.

Download or read book Evidence for WZ Production and a Measurement of the WZ Production Cross Section written by and published by . This book was released on 2007 with total page 181 pages. Available in PDF, EPUB and Kindle. Book excerpt: This dissertation describes a test of the Standard Model (SM) of particle physics by measuring the probability, or cross section, of simultaneously producing a W boson and a Z boson from proton-antiproton collisions. The SM predicts the cross section of WZ production to be 3.68 ± 0.25 pb. The SM and physics of WZ production are described in Chapter 2 of this dissertation. The 1.96 TeV center-of-mass energy proton-antiproton collisions are provided by the Fermi National Accelerator Laboratory (FNAL) Tevatron Collider. The W and Z particles are detected using the D0 detector, which is described in Chapter 3. The data were collected by the detector during 2002-2006 corresponding to 1 fb−1 of p{bar p} collisions. This data set is described in Chapter 6. The measurement uses the trilepton (e[nu]ee, [mu][nu]ee, e[nu][mu][mu], and [mu][nu][mu][mu]) decay channels, in which a W decays to a charged lepton plus a neutrino and a Z decays to a pair of charged leptons. The W and Z particle selection criteria, detection efficiency, and background determination are described in Chapter 7. We observe 13 candidate events in 1 fb−1 of p{bar p} collisions. In this data set we expect to see 4.5 ± 0.6 background events, and we expect to see 9.2 ± 1.0 signal events. The probability of 4.5 ± 0.6 background events to fluctuate to 13 or more events is 1.2 x 10−3 which is a 3.0 [sigma] deviation from the background estimate. A log likelihood method is used to determine the most likely cross section as determined by the measured signal efficiencies, the expected backgrounds, and the observed data. Presented in Chapter 8 is a measurement of the cross section for p{bar p} → WZ + X at √s = 1.96 TeV. The WZ diboson production cross section is measured to be [sigma]{sub WZ} = 2.7{sub -1.3}{sup +1.7} pb. This is in agreement with the predicted Standard Model cross section.

Download or read book Measurement of the W Z Boson Pair production Cross Section in Pp Collisions at written by and published by . This book was released on 2016 with total page 22 pages. Available in PDF, EPUB and Kindle. Book excerpt: Here, the production of W±Z events in proton–proton collisions at a centre-of-mass energy of 13 TeV13 TeV is measured with the ATLAS detector at the LHC. The collected data correspond to an integrated luminosity of 3.2 fb–1. The W±Z candidates are reconstructed using leptonic decays of the gauge bosons into electrons or muons.

Download or read book A Measurement of the W W Production Cross section in Pp Collisions at U 221a s written by Dustin James McGivern and published by . This book was released on 2005 with total page 0 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Measurement of the W Z Boson Pair production Cross Section in Pp Collisions at mml written by and published by . This book was released on 2016 with total page 22 pages. Available in PDF, EPUB and Kindle. Book excerpt: Here, the production of W±Z events in proton-proton collisions at a centre-of-mass energy of 13 TeV13 TeV is measured with the ATLAS detector at the LHC. The collected data correspond to an integrated luminosity of 3.2 fb-1. The W±Z candidates are reconstructed using leptonic decays of the gauge bosons into electrons or muons.