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 Measurement of W Boson Production in Pb Pb Collisions at 5 02 TeV with the ATLAS Detector written by Piotr Janus 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 A Measurement of W Boson Pair Production in Pp Collisions at Sqrt 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: Zusammenfassung: In this thesis, measurements of the W boson pair production cross section in proton-proton collisions at a centre-of-mass energy of 8 TeV are presented. A dataset corresponding to an integrated luminosity of 22.3 /fb recorded by the ATLAS experiment in the year 2012 is used. The W bosons are identified by their decay products of exactly two leptons with opposite electrical charge, electrons or muons, and missing transverse momentum induced by their corresponding neutrinos. First, a measurement restricted to final states without hadronic jets is presented and differential fiducial cross sections, total cross sections and limits on anomalous triple gauge boson couplings are obtained. A second measurement of the fiducial cross section in association with exactly one hadronic jet is presented. The ratio of fiducial cross sections for different jet multiplicities is reported and the combined fiducial cross section is extrapolated to the total phase space.
Download or read book Measurement of the Production Cross section of Two W Bosons from Seven trillion electronvolt Center of mass energy Proton proton Collisions written by Jacob Thomas Ribnik and published by . This book was released on 2011 with total page 177 pages. Available in PDF, EPUB and Kindle. Book excerpt: This dissertation describes the first WW production cross-section measurement in 35.5 pb-1 of s = 7 TeV pp collision data recorded by the CMS detector. The ee, emu and mumu final states are considered. The event yields, expectations and systematic uncertainties arc presented, and the data-driven methods used to estimate the background and selection efficiency are discussed in detail. The cross-section is measured to be sigmaWW = 41.1 +/- 15.3(stat.) +/- 5.8(syst.) +/- 4.5(lumi.) pb. The same data is used to place constraints on anomalous WWgamma and WWZ couplings.
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 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 Generator level Acceptance for the Measurement of the Inclusive Cross Section of W boson and Z boson Production in Pp Collisions at square Root Of S written by Alexander Andriatis and published by . This book was released on 2018 with total page 42 pages. Available in PDF, EPUB and Kindle. Book excerpt: The inclusive cross section of vector boson production in proton-proton collisions is one of the key measurements for constraining the Standard Model and an important part of the physics program at the LHC. Measurement of the inclusive cross section requires calculating the detector acceptance of decay products. The acceptance of the CMS detector of leptonic decays of W and Z bosons produced in pp colisions at [square root of]s = 5 TeV is calculated using Monte Carlo event simulation. Statistical and systematic uncertainties on the acceptance measurement from PDF and a, uncertainty and higher-order correction are reported. The use of the calculated acceptance in combination with measurements of detector efficiency, luminosity, and particle counting to determine the inclusive cross section is outlined. A total integrated luminosity of 331.64 pb-1 from 2015 and 2017 CMS data at [square root of]s = 5 TeV is available for the calculation of the inclusive cross section.
Download or read book A Search for Displaced Leptons in the ATLAS Detector written by Lesya Horyn and published by Springer Nature. This book was released on 2022-02-07 with total page 146 pages. Available in PDF, EPUB and Kindle. Book excerpt: This thesis presents a search for long-lived particles decaying into displaced electrons and/or muons with large impact parameters. This signature provides unique sensitivity to the production of theoretical lepton-partners, sleptons. These particles are a feature of supersymmetric theories, which seek to address unanswered questions in nature. The signature searched for in this thesis is difficult to identify, and in fact, this is the first time it has been probed at the Large Hadron Collider (LHC). It covers a long-standing gap in coverage of possible new physics signatures. This thesis describes the special reconstruction and identification algorithms used to select leptons with large impact parameters and the details of the background estimation. The results are consistent with background, so limits on slepton masses and lifetimes in this model are calculated at 95% CL, drastically improving on the previous best limits from the Large Electron Positron Collider (LEP).
Download or read book W Boson Production in bar P p Collisions At Sqrt S written by and published by . This book was released on 1988 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: The cross section for the production and subsequent decay of the W Intermediate Vector boson to electron and neutrino has been measured in .sqrt.s = 1.8 TeV /bar p/p collisions using the CDF Collider Detector at Fermilab. For this measurement, W events were identified from the large missing transverse energy associated with the unseen neutrino and an electromagnetic cluster passing rather loose electron criteria. 22 events passing the selection missing transverse energy greater than 25 GeV and electron transverse energy greater than 15 GeV were observed in a sample of 25nb/sup /minus/1/ yielding a sigma /center dot/ B = 2.6 ± 0.6 ± 0.5nb. This report agrees well with a parallel analysis based primarily on the identification of isolated electron and is in excellent agreement with theoretical predictions. 12 refs., 7 figs.
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.
Download or read book Measurement of VH H Bb Production as a Function of the Vector boson Transverse Momentum in 13 TeV Pp Collisions with the ATLAS Detector written by Anne Kathrin Becker and published by . This book was released on 2019 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: Abstract: Cross-sections of associated production of a Higgs boson decaying into bottomquark pairs and an electroweak gauge boson, W or Z, decaying into leptons are measured as a function of the gauge boson transverse momentum. The measurements are performed in kinematic fiducial volumes defined in the 'simplified template cross-section' framework. The results are obtained using 79.8 fb−1 of proton-proton collisions recorded by the ATLAS detector at the Large Hadron Collider at a centre-of-mass energy of 13 TeV. All measurements are found to be in agreement with the Standard Model predictions, and limits are set on the parameters of an effective Lagrangian sensitive to modifications of the Higgs boson couplings to the electroweak gauge bosons
Download or read book Particle Physics Reference Library written by Herwig Schopper and published by Springer Nature. This book was released on 2020 with total page 632 pages. Available in PDF, EPUB and Kindle. Book excerpt: This first open access volume of the handbook series contains articles on the standard model of particle physics, both from the theoretical and experimental perspective. It also covers related topics, such as heavy-ion physics, neutrino physics and searches for new physics beyond the standard model. A joint CERN-Springer initiative, the "Particle Physics Reference Library" provides revised and updated contributions based on previously published material in the well-known Landolt-Boernstein series on particle physics, accelerators and detectors (volumes 21A, B1,B2,C), which took stock of the field approximately one decade ago. Central to this new initiative is publication under full open access
Download or read book Higgs Boson Decays into a Pair of Bottom Quarks written by Cecilia Tosciri and published by Springer Nature. This book was released on 2021-10-22 with total page 171 pages. Available in PDF, EPUB and Kindle. Book excerpt: The discovery in 2012 of the Higgs boson at the Large Hadron Collider (LHC) represents a milestone for the Standard Model (SM) of particle physics. Most of the SM Higgs production and decay rates have been measured at the LHC with increased precision. However, despite its experimental success, the SM is known to be only an effective manifestation of a more fundamental description of nature. The scientific research at the LHC is strongly focused on extending the SM by searching, directly or indirectly, for indications of New Physics. The extensive physics program requires increasingly advanced computational and algorithmic techniques. In the last decades, Machine Learning (ML) methods have made a prominent appearance in the field of particle physics, and promise to address many challenges faced by the LHC. This thesis presents the analysis that led to the observation of the SM Higgs boson decay into pairs of bottom quarks. The analysis exploits the production of a Higgs boson associated with a vector boson whose signatures enable efficient triggering and powerful background reduction. The main strategy to maximise the signal sensitivity is based on a multivariate approach. The analysis is performed on a dataset corresponding to a luminosity of 79.8/fb collected by the ATLAS experiment during Run-2 at a centre-of-mass energy of 13 TeV. An excess of events over the expected background is found with an observed (expected) significance of 4.9 (4.3) standard deviation. A combination with results from other \Hbb searches provides an observed (expected) significance of 5.4 (5.5). The corresponding ratio between the signal yield and the SM expectation is 1.01 +- 0.12 (stat.)+ 0.16-0.15(syst.). The 'observation' analysis was further extended to provide a finer interpretation of the V H(H → bb) signal measurement. The cross sections for the VH production times the H → bb branching ratio have been measured in exclusive regions of phase space. These measurements are used to search for possible deviations from the SM with an effective field theory approach, based on anomalous couplings of the Higgs boson. The results of the cross-section measurements, as well as the constraining of the operators that affect the couplings of the Higgs boson to the vector boson and the bottom quarks, have been documented and discussed in this thesis. This thesis also describes a novel technique for the fast simulation of the forward calorimeter response, based on similarity search methods. Such techniques constitute a branch of ML and include clustering and indexing methods that enable quick and efficient searches for vectors similar to each other. The new simulation approach provides optimal results in terms of detector resolution response and reduces the computational requirements of a standard particles simulation.
Download or read book Particle Physics Reference Library written by Christian W. Fabjan and published by Springer Nature. This book was released on 2020 with total page 1083 pages. Available in PDF, EPUB and Kindle. Book excerpt: This second open access volume of the handbook series deals with detectors, large experimental facilities and data handling, both for accelerator and non-accelerator based experiments. It also covers applications in medicine and life sciences. A joint CERN-Springer initiative, the "Particle Physics Reference Library" provides revised and updated contributions based on previously published material in the well-known Landolt-Boernstein series on particle physics, accelerators and detectors (volumes 21A, B1,B2,C), which took stock of the field approximately one decade ago. Central to this new initiative is publication under full open access
Download or read book Measurements of ZH and WH Production in the H Bb Decay Channel in Pp Collisions at 13 TeV with the ATLAS Detector written by ATLAS Collaboration CERN and published by . This book was released on 2020 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: Abstract: Measurements are presented of the Standard Model Higgs boson decaying into a bb ̄ pair and produced in association with a W or Z boson decaying into leptons, using proton-proton collision data collected between 2015 and 2018 by the ATLAS detector. The measurements use data delivered by the Large Hadron Collider at a centre-of-mass energy of s√=13 TeV, corresponding to an integrated luminosity of 139 fb−1. The production of a Higgs boson in association with a W or Z boson is established, with observed (expected) significances of 4.0 (4.1) and 5.3 (5.1) standard deviations, respectively. Cross-sections of associated production of a Higgs boson decaying into bottom quark pairs with an electroweak gauge boson, W or Z, decaying into leptons are measured as a function of the gauge boson transverse momentum in kinematic fiducial volumes. The cross-section measurements are all consistent with the Standard Model expectations, and the total uncertainties vary from 30% in the high gauge boson transverse momentum regions to 85% in the low regions
Download or read book The Standard Model Higgs Boson written by Martin B. Einhorn and published by North Holland. This book was released on 1991 with total page 408 pages. Available in PDF, EPUB and Kindle. Book excerpt: Volume 8.
Download or read book Measurement of the W Charge Asymmetry in the Pp Collisions at arrow written by and published by . This book was released on 2011 with total page 19 pages. Available in PDF, EPUB and Kindle. Book excerpt: This letter reports a measurement of the muon charge asymmetry from W Boson produced in proton-proton collisions at a centre-of-mass energy of 7 TeV with the ATLAS experiment at the LHC. The asymmetry is measured in the W → [mu][nu] decay mode as a function of the muon pseudorapidity using a data sample corresponding to a total integrated luminosity of 31 pb-1. The results are compared to predictions based on next-to-leading order calculations with various parton distribution functions. The measurement provides information on the u and d quark momentum fractions in the proton.
