Download or read book Measurement of W and Z Boson Production Cross Sections in Proton proton Collisions at square Root S written by Stephanie Akemi Brandt and published by . This book was released on 2020 with total page 160 pages. Available in PDF, EPUB and Kindle. Book excerpt: Measurements of W and Z boson production cross sections in pp collisions at [square root] s = 5.02TeV and [square root] s = 13TeV are presented. Data was collected by the CMS experiment at the LHC during low-pileup data taking periods in 2017. The corresponding integrated luminosity for the data is 299.1 ± 5 pb−1 ( [square root] s = 5.02TeV) and 199.3 ± 4 pb−1 ( [square root] s = 13TeV), with an average number of pile-up interactions [[mu] = 3 ([mu] = 2). Cross sections and cross section ratios are reported, with final states in electron and muon channels.

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 Measurement of the W and Z Boson Production Cross Sections in P P Collisions at square Root Sign s written by Peter Matthew Grudberg and published by . This book was released on 1997 with total page 400 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Measurement of the Production Cross Sections for a Z Boson and One Or More B Jets in Pp Collisions at Sqrt s written by and published by . This book was released on 2014 with total page 39 pages. Available in PDF, EPUB and Kindle. Book excerpt: The production of a Z boson, decaying into two leptons and produced in association with one or more b jets, is studied using proton-proton collisions delivered by the LHC at a centre-of-mass energy of 7 TeV. The data were recorded in 2011 with the CMS detector and correspond to an integrated luminosity of 5 fb-1. The Z(ll) + b-jets cross sections (where ll = [mu][mu] or ee) are measured separately for a Z boson produced with exactly one b jet and with at least two b jets. In addition, a cross section ratio is extracted for a Z boson produced with at least one b jet, relative to a Z boson produced with at least one jet. The measured cross sections are compared to various theoretical predictions, and the data favour the predictions in the five-flavour scheme, where b quarks are assumed massless. The kinematic properties of the reconstructed particles are compared with the predictions from the MadGraph event generator using the pythia parton shower simulation.

Download or read book Measurement of WZ and ZZ Production 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: Measurements are reported of the WZ and ZZ production cross sections in proton-proton collisions at $\sqrt{s}$ = 8 TeV in final states where one Z boson decays to b-tagged jets. The other gauge boson, either W or Z, is detected through its leptonic decay (either $W \to e\nu, \mu\nu$ or $Z \to e^+ e^-, \mu^+ \mu^-$, or $\nu\bar{\nu})$. The results are based on data corresponding to an integrated luminosity of 18.9 inverse-femtobarns collected with the CMS detector at the Large Hadron Collider. The measured cross sections, $\sigma(pp \to WZ)$ = 30.7 $\pm$ 9.3 (stat.) $\pm$ 7.1 (syst.) $\pm$ 4.1 (th.) $\pm$ 1.0 (lum.) pb and $\sigma(pp \to ZZ)$ = 6.5 $\pm$ 1.7 (stat.) $\pm$ 1.0 (syst.) $\pm$ 0.9 (th.) $\pm$ 0.2 (lum.) pb, are consistent with next-to-leading order quantum chromodynamics calculations.

Download or read book Measurement of Inclusive W and Z Boson Production Cross Sections in Pp Collisions at sqrt s written by and published by . This book was released on 2014 with total page 31 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Measurement of the Z tau tau Production Cross section in Proton proton Collisions at square Root Of S written by Justin Griffiths and published by . This book was released on 2012 with total page 137 pages. Available in PDF, EPUB and Kindle. Book excerpt: The first measurement of the inclusive cross-section of the Z boson decaying to two tau leptons was measured with the ATLAS detector at the LHC. The data sample in this analysis represents an integrated luminosity of 35 pb ̄1 of proton-proton collisions at a center of mass energy of sqrt(s)=7 TeV. Separate measurements were performed in four decay modes based on how the two tau leptons decay: to hadrons and an electron, to hadrons and a muon, to an electron and a muon, and to two muons. In all four final states, inclusive cross-section measurements were made both in the fiducial region of the ATLAS detector where acceptance is high and in the full phase space, restricted to the mass range of [66, 116] GeV. The measurements from the four individual channels were then combined to yield the combined Z --> [tau] [tau] cross-section of 970 ± 70 (stat.) ± 60 (sys.) ± 30 (lumi.) pb.

Download or read book Measurement of the ZZ Production Cross Section in pp Collisions at sqrt s written by and published by . This book was released on 2016 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: The ZZ production cross section in proton-proton collisions at 13 TeV center-of-mass energy is measured using 3.2 fb–1 of data recorded with the ATLAS detector at the Large Hadron Collider. The considered Z boson candidates decay to an electron or muon pair of mass 66–116 GeV. The cross section is measured in a fiducial phase space reflecting the detector acceptance. It is also extrapolated to a total phase space for Z bosons in the same mass range and of all decay modes, giving 16.7+2.2–2.0(stat)+0.9–0.7(syst)+1.0–0.7(lumi) pb. Lastly, the results agree with standard model predictions.

Download or read book A Measurement of W Boson photon and Z Boson photon Cross Sections in the Muon Channel in 1 8 TeV Proton antiproton Collisions written by Christopher B. Luchini and published by . This book was released on 1994 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: We have measured the production cross sections x decay branching ratios for W + $gamma$ and Z + $gamma$ in the muon channel in $sqrt{s}$ = 1.8 TeV p-p collisions, from 3.54 $pm$ 0.24 $pbsp{-1}$ of muon W and Z data from the CDF 1988-89 Tevatron collider run. For photons in the central region ($vertetavert $ 5.0 GeV and lepton-photon angular separation $Delta Rsb{ellsbgamma} >$ 0.7, 5 $Wsb{gamma}$ candidates and 2 $Zsb{gamma}$ candidates were observed. From these events, the $sigma cdot BR(W + gamma)$ and $sigma cdot BR(Z + gamma)$ cross sections for the muon samples are measured, and compared with Standard Model predictions. We also determined the cross section ratios, $Wsb{gamma}$/W, $Zsb{gamma}$/Z and $Wsb{gamma}/Zsb{gamma}$, which, along with the previous CDF measurement(s) of the W/Z cross section ratio provide new insight on the Standard Model, and are sensitive to anomalous couplings of the W and Z bosons. Using the $Wsb{gamma}$ and $Zsb{gamma}$ absolute cross section measurements, the absence of an excess of hard photons accompanying W and Z boson production enables us to obtain direct limites on anomalous $WWsb{gamma}$, $ZZsb{gamma}$ and $Zsb{gammagamma}$ couplings. For saturation of unitarity, these experimental limits impose constraints on possible internal (composite) structure for the W and Z bosons with compositeness scale sensitivity up to $Lambdasb{W} sim$ 1 TeV and $Lambdasb{Z} sim$ 250-500 GeV, respectively. These compositeness scale limits probe the possible internal structure of the W to ${sim}

Download or read book Z Boson Cross Section Measurements and Neutral Higgs Boson Search in the Di muon Channel with the CMS Detector written by Xinmei Niu (Ph. D.) and published by . This book was released on 2019 with total page 186 pages. Available in PDF, EPUB and Kindle. Book excerpt: In this thesis, measurements of inclusive and differential Z boson production cross sections in proton-proton collisions at [square root of] s =13 TeV with the CMS detector at Large Hadron Collider are performed with the di-muon channel. The measured total inclusive cross section times branching ratio is or(pp - ZX) x [beta](Z --> [mu][mu]) = 1870 ± 2(stat) ± 35(syst) ± 51(lumi) pb for the di-muon invariant mass in the range of 60 to 120 GeV, which is in good agreement with the next-to-next-to leading order QCD predictions. The spectra of Z boson transverse momentum, ... variable, rapidity, and the muon transverse momentum are also measured and compared with theoretical predictions. The large production cross section of Z boson and good experimental accessibility of final-state muons permit a real-time monitoring of luminosities using the counts of reconstructed Z --> [mu][mu] events. Preliminary results of counting of Z bosons as a luminometer are shown using the entire 2018 data-taking period. A search for beyond Standard Model neutral Higgs bosons decaying to two muons is also presented. No significant excess is observed. A 95% confidence level upper limit is set on ... The exclusion contour is also determined on the parameter phase space in the context of Minimal Supersymmetric Standard Mode representative benchmark scenarios.

Download or read book Measurements of Inclusive W and Z Cross Sections in Pp Collisions at Sqrt s written by and published by . This book was released on 2011 with total page 38 pages. Available in PDF, EPUB and Kindle. Book excerpt: Measurements of inclusive W and Z boson production cross sections in pp collisions at sqrt(s)=7 TeV are presented, based on 2.9 inverse picobarns of data recorded by the CMS detector at the LHC. The measurements, performed in the electron and muon decay channels, are combined to give sigma(pp to WX) times B(W to muon or electron + neutrino) = 9.95 \pm 0.07(stat.) \pm 0.28(syst.) \pm 1.09(lumi.) nb and sigma(pp to ZX) times B(Z to oppositely charged muon or electron pairs) = 0.931 \pm 0.026(stat.) \pm 0.023(syst.) \pm 0.102(lumi.) nb. Theoretical predictions, calculated at the next-to-next-to-leading order in QCD using recent parton distribution functions, are in agreement with the measured cross sections. Ratios of cross sections, which incur an experimental systematic uncertainty of less than 4%, are also reported.

Download or read book Measurement of Associated Z Boson and Charm Quark Production in Proton proton Collisions at Square Root of S Equals to 13 TeV written by Luis Pinto Cabrera and published by . This book was released on 2020 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: "This thesis presents the measurements of the differential production cross-sections of a Z boson in association with at least one charm-quark-initiated jet, where the Z boson decays leptonically into a muon-antimuon pair. Data recorded in proton-proton collisions by the ATLAS detector at the Large Hadron Collider (LHC) during the years of 2015 to 2018 is utilised, when the LHC was running at a center of mass energy of 13 TeV. The studied data corresponds to a total integrated luminosity of 139 fb^-1. The measurements are compared to simulated data produced at next-to-leading-order and normalized to theoretical predictions at next-to-next-leading order. The results show that predictions underestimate the total number of events by 50% but display a good modelling of all distribution shapes of the chosen observables in data. The discrepancy can be attributed to a problem in the normalisation but further studies need to be made to settle the issue"--

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 Measurements of the Differential Production Cross Sections for a Z Boson in Association with Jets in Pp Collisions at sqrt s written by and published by . This book was released on 2016 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: Cross sections for the production of a Z boson in association with jets in proton-proton collisions at a centre-of-mass energy of $\sqrt{s}$=8 TeV are measured using a data sample collected by the CMS experiment at the LHC corresponding to 19.6 inverse femtobarns. Differential cross sections are presented as functions of up to three observables that describe the jet kinematics and the jet activity. Correlations between the azimuthal directions and the rapidities of the jets and the Z boson are studied in detail. The predictions of a number of multileg generators with leading or next-to-leading order accuracy are compared with the measurements. The comparison shows the importance of including multi-parton contributions in the matrix elements and the improvement in the predictions when next-to-leading order terms are included.

Download or read book Measurement of the W W Cross Section in Pp Collisions at sqrt s written by and published by . This book was released on 2015 with total page 42 pages. Available in PDF, EPUB and Kindle. Book excerpt: A measurement of the W boson pair production cross section in proton-proton collisions at [arrow]"s = 8 TeV is presented. The data we collected with the CMS detector at the LHC correspond to an integrated luminosity of 19.4 fb-1 . The W+W- candidates are selected from events with two charged leptons, electrons or muons, and large missing transverse energy. The measured W+W- cross section is 60.1 " 0.9 (stat) " 3.2 (exp) " 3.1 (theo) " 1.6 (lumi) pb = 60.1 " 4.8 pb, consistent with the standard model prediction. The W+W-cross sections are also measured in two different fiducial phase space regions. The normalized differential cross section is measured as a function of kinematic variables of the final-state charged leptons and compared with several perturbative QCD predictions. Limits on anomalous gauge couplings associated with dimension-six operators are also given in the framework of an effective field theory. Finally, the corresponding 95% confidence level intervals are -5.7

Download or read book Measurement of Total and Differential W W Production Cross Sections in Proton proton Collisions at sqrt s written by and published by . This book was released on 2016 with total page 81 pages. Available in PDF, EPUB and Kindle. Book excerpt: The production of W boson pairs in proton-proton collisions at √s = 8 TeV is studied using data corresponding to 20.3 fb-1 of integrated luminosity collected by the ATLAS detector during 2012 at the CERN Large Hadron Collider. The W bosons are reconstructed using their leptonic decays into electrons or muons and neutrinos. Events with reconstructed jets are not included in the candidate event sample. A total of 6636 WW candidate events are observed. Measurements are performed in fiducial regions closely approximating the detector acceptance. The integrated measurement is corrected for all acceptance effects and for the W branching fractions to leptons in order to obtain the total WW production cross section, which is found to be 71.1 ± 1.1(stat)-5.0+ 5.7(syst) ± 1.4(lumi) pb. This agrees with the next-to-next-to-leading-order Standard Model prediction of 63.2-1.4+1.6(scale) ± 1.2(PDF) pb. Fiducial differential cross sections are measured as a function of each of six kinematic variables. In conclusion, the distribution of the transverse momentum of the leading lepton is used to set limits on anomalous triple-gauge-boson couplings.

Download or read book Inclusive Electroweak Measurements in the Muon Channel with Pp Collisions at the Square Root Of S written by Philip Coleman Harris and published by . This book was released on 2011 with total page 243 pages. Available in PDF, EPUB and Kindle. Book excerpt: In this thesis, we perform the measurement of the production of W and Z bosons in proton-proton collisions at [the square root of]s = 7 TeV with the Large Hadron Collider (LHC). In the LHC, W and Z bosons are produced at a high rate, providing for large yields, which along with the clean signature of W boson decay into a muon and neutrino and the Z boson decay into two muons, allow for precision measurement of their production within the first year of operation. Deviation of these values from standard model predictions gives a clear indication of new physics interactions occurring at the LHC. We present the measurement of the inclusive W--> [mu] [epsilon] and Z --> [mu]+ [mu]- cross sections along with the W boson charge ratio (W+/W-) and the W/Z production ratio in the muon channel using the first data corresponding to 35.9 pb-1 of proton proton collisions at [the square root of]s = 7 TeV. Measured values of ... are in agreement with the most advanced NNLO predictions. These are currently the most precise Electroweak measurements at the LHC.