EBookClubs

Read Books & Download eBooks Full Online

EBookClubs

Read Books & Download eBooks Full Online

Book Cross Section Measurements for process Studies Using a LEPS Detector

Download or read book Cross Section Measurements for process Studies Using a LEPS Detector written by and published by . This book was released on 2016 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt:

Book Measurement of the Double Differential Diject Mass Cross Section in P bar p Collisions at u221A s

Download or read book Measurement of the Double Differential Diject Mass Cross Section in P bar p Collisions at u221A s written by and published by . This book was released on 2009 with total page 176 pages. Available in PDF, EPUB and Kindle. Book excerpt: This thesis presents the analysis of the double differential dijet mass cross section, measured at the D0 detector in Batavia, IL, using p$ar{p}$ collisions at a center of mass energy of √s = 1.96 TeV. The dijet mass was calculated using the two highest pT jets in the event, with approximately 0.7 fb-1 of data collected between 2004 and 2005. The analysis was presented in bins of dijet mass (MJJ) and rapidity (y), and extends the measurement farther in MJJ and y than any previous measurement. Corrections due to detector effects were calculated using a Monte Carlo simulation and applied to data. The errors on the measurement consist of statistical and systematic errors, of which the Jet Energy Scale was the largest. The final result was compared to next-to-leading order theory and good agreement was found. These results may be used in the determination of the proton parton distribution functions and to set limits on new physics.

Book Measurement of the Cross Section for W boson Production in Association with Jets in Ppbar Collisions at S

Download or read book Measurement of the Cross Section for W boson Production in Association with Jets in Ppbar Collisions at S written by and published by . This book was released on 2007 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: We present a measurement of the cross section for W-boson production in association with jets in p{bar p} collisions at √s = 1.96 TeV. The analysis uses a data sample corresponding to an integrated luminosity of 320 pb−1 collected with the CDF II detector. W bosons are identified in their electron decay channel and jets are reconstructed using a cone algorithm. For each W + ≥ n-jet sample (n = 1-4) we measure?(p{bar p} → W + ≥ n-jet) x?(W → e?) with respect to the transverse energy E{sub T} of the nth-highest E{sub T} jet above 20 GeV, for a restricted W → e? decay phase space. The cross sections, corrected for all detector effects, can be directly compared to particle level W + jet(s) predictions. We present here comparisons to leading order and next-to-leading order predictions.

Book Measurement of the Double Differential Diject Mass Cross Section in Pp bar Collisions at Sqrt s

Download or read book Measurement of the Double Differential Diject Mass Cross Section in Pp bar Collisions at Sqrt s written by and published by . This book was released on 2009 with total page 176 pages. Available in PDF, EPUB and Kindle. Book excerpt: This thesis presents the analysis of the double differential dijet mass cross section, measured at the D0 detector in Batavia, IL, using p{bar p} collisions at a center of mass energy of (square root)s = 1.96 TeV. The dijet mass was calculated using the two highest p{sub T} jets in the event, with approximately 0.7 fb−1 of data collected between 2004 and 2005. The analysis was presented in bins of dijet mass (M{sub JJ}) and rapidity (y), and extends the measurement farther in M{sub JJ} and y than any previous measurement. Corrections due to detector effects were calculated using a Monte Carlo simulation and applied to data. The errors on the measurement consist of statistical and systematic errors, of which the Jet Energy Scale was the largest. The final result was compared to next-to-leading order theory and good agreement was found. These results may be used in the determination of the proton parton distribution functions and to set limits on new physics.

Book Hadronic Cross Section Measurements on the Z Resonance with the L3 Detector

Download or read book Hadronic Cross Section Measurements on the Z Resonance with the L3 Detector written by Frank Filthaut and published by . This book was released on 1993 with total page 113 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Book Measurement of the mathrm T bar t Production Cross Section in the mathrm E mu Channel in Proton proton Collisions at sqrt s

Download or read book Measurement of the mathrm T bar t Production Cross Section in the mathrm E mu Channel in Proton proton Collisions at sqrt s written by and published by . This book was released on 2016 with total page 54 pages. Available in PDF, EPUB and Kindle. Book excerpt: The inclusive cross section for top quark pair production is measured in proton-proton collisions at √s = 7 and 8 TeV, corresponding to 5.0 and 19.7 fb-1, respectively, with the CMS experiment at the LHC. The cross sections are measured in the electron-muon channel using a binned likelihood fit to multi-differential final state distributions related to identified b quark jets and other jets in the event. The measured cross section values are 173.6 ± 2.1 (stat)+4.5-4.0 (syst) ± 3.8 (lumi) pb at √s = 7 TeV, and 244.9 ± 1.4 (stat)+6.3-5.5 (syst) ± 6.4 (lumi) pb at √s = 8 TeV, in good agreement with QCD calculations at next-to-next-to-leading-order accuracy. The ratio of the cross sections measured at 7 and 8 TeV is determined, as well as cross sections in the fiducial regions defined by the acceptance requirements on the two charged leptons in the final state. The cross section results are used to determine the top quark pole mass via the dependence of the theoretically predicted cross section on the mass, giving a best result of 173.8+1.7-1.8 GeV. Furthermore, the data at √s = 8 TeV are also used to set limits, for two neutralino mass values, on the pair production of supersymmetric top squarks with masses close to the top quark mass.

Book Measurement of the W W Cross Section in arrow

Download or read book Measurement of the W W Cross Section in arrow written by and published by . This book was released on 2011 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: This Letter presents a measurement of the W+W- production cross section in [arrow]" = 7 TeV pp collisions by the ATLAS experiment, using 34 inverse pb-1 of integrated luminosity produced by the Large Hadron Collider at CERN. Selecting events with two isolated leptons, each either an electron or a muon, 8 candidate events are observed with an expected background of 1.7"0.6 events. The measured cross section is 41+20-16(stat) " 5(syst) " 1(lumi) pb, which is consistent with the standard model prediction of 44 " 3 pb calculated at next-to-leading order in QCD.

Book Measurements of W Z Production Cross Sections in Pp Collisions at S

Download or read book Measurements of W Z Production Cross Sections 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: This study presents measurements of W±Z production in pp collisions at a center-of-mass energy of 8 TeV. The gauge bosons are reconstructed using their leptonic decay modes into electrons and muons. The data were collected in 2012 by the ATLAS experiment at the Large Hadron Collider and correspond to an integrated luminosity of 20.3 fb-1. The measured inclusive cross section in the detector fiducial region is ?W±Z→l'?ll = 35.1 ± 0.9(stat) ± 0.8(sys) ± 0.8(lumi) fb, for one leptonic decay channel. In comparison, the next-to-leading-order Standard Model expectation is 30.0 ± 2.1 fb. Cross sections for W+Z and W-Z production and their ratio are presented as well as differential cross sections for several kinematic observables. Limits on anomalous triple gauge boson couplings are derived from the transverse mass spectrum of the W±Z system. From the analysis of events with a W and a Z boson associated with two or more forward jets an upper limit at 95% confidence level on the W±Z scattering cross section of 0.63 fb, for each leptonic decay channel, is established, while the Standard Model prediction at next-to-leading order is 0.13 ± 0.01 fb. Limits on anomalous quartic gauge boson couplings are also extracted.

Book Measurement of the Cross Section for W boson Production in Association with Jets in Ppbar Collisions at S 1 2

Download or read book Measurement of the Cross Section for W boson Production in Association with Jets in Ppbar Collisions at S 1 2 written by and published by . This book was released on 2007 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: We present a measurement of the cross section for W-boson production in association with jets in p{bar p} collisions at √s = 1.96 TeV. The analysis uses a data sample corresponding to an integrated luminosity of 320 pb−1 collected with the CDF II detector. W bosons are identified in their electron decay channel and jets are reconstructed using a cone algorithm. For each W + ≥ n-jet sample (n = 1-4) we measure [sigma](p{bar p} → W + ≥ n-jet) x [Beta](W → e[nu]) with respect to the transverse energy E{sub T} of the nth-highest E{sub T} jet above 20 GeV, for a restricted W → e[nu] decay phase space. The cross sections, corrected for all detector effects, can be directly compared to particle level W + jet(s) predictions. We present here comparisons to leading order and next-to-leading order predictions.

Book Measurement of Differential Cross Sections in the T bar t u2192 L jets Channel at u221A s

Download or read book Measurement of Differential Cross Sections in the T bar t u2192 L jets Channel at u221A s written by and published by . This book was released on 2009 with total page 298 pages. Available in PDF, EPUB and Kindle. Book excerpt: The analysis presented in this thesis focuses on kinematic distributions in the t$ar{t}$ system and studies in detail selected differential cross sections of top quarks as well as the reconstructed t$ar{t}$ pair, namely the top quark transverse momentum and the t$ar{t}$ system mass. The structure of the thesis is organized as follows: first the Standard Model of the particle physics is briefly introduced in Chapter 1, with relevant aspects of electroweak and strong interactions discussed. The physics of the top quark and its properties are then outlined in Chapter 2, together with the motivation for measuring the transverse top quark momentum and other kinematic-related variables of the t$ar{t}$ system. The concepts of present-day high energy physics collider experiments and the explicit example of Fermilab Tevatron collider and the D0 detector in Chapters 3 and 4 are followed by the description of basic detector-level objects, id est tracks, leptons and jets, in Chapter 5; their identification and calibration following in next chapter with the emphasis on the jet energy scale in Chapter 6 and jet identification at the D0. The analysis itself is outlined in Chapter 7 and is structured so that first the data and simulation samples and the basic preselection are described in Chapter 8 and 9, followed by the kinematic reconstruction part in Chapter 10. Chapter 11 on background normalization and Chapter 12 with raw reconstructed spectra results (at the detector-smeared level) are followed by the purity-based background subtraction method and examples of signal-level corrected spectra in Chapter 13. Next, the procedure of correcting measured spectra for detector effects (unfolding) is described in Chapters 14-15, including migration matrix studies, acceptance correction determination as well as the regularized unfolding procedure itself. Final differential cross sections are presented in Chapter 16 with the main results in Figures 16.19-16.20. Summary and discussion close the main analysis part in Chapter 17, supplemented by appendices on the wealthy of analysis control plots of the t$ar{t}$ → l + jets channel, selected D0 event displays and finally the list of publications and references. Preliminary results of this analysis have been documented in D0 internal notes [UnfoldTop], [p17Top], [p14Top]; as well as presented at conferences [APS08], [APS05]. The author has also been a co-author of more than 135 D0 collaboration publications since 2005. The author has taken part in the jet energy scale calibration efforts performing final closure tests and deriving a correction to jet energy offset due to the suppression of the calorimeter signal. The author has also co-performed the ?-intercalibration of the hadronic calorimeter and co-supervised the electromagnetic ?-intercalibration; recently has also been involved in maintaining the jet identification efficiencies measurement as a JetID convener. During the years in Fermilab, many events have taken place in the course of the analysis in persuasion, including more than 170 shifts served for the D0 detector with or without the beam, 168 talks presented with mixed results and reactions; and tens of thousands of code lines in C (and sometimes perhaps even really C++) written while terabytes of data were processed, analyzed, and sometimes also lost. It has been a long but profoundly enriching chapter of my life.

Book Measurement of the Production and Differential Cross Sections of W W Bosons in Association with Jets in p bar p Collisions at sqrt s

Download or read book Measurement of the Production and Differential Cross Sections of W W Bosons in Association with Jets in p bar p Collisions at sqrt s written by and published by . This book was released on 2015 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: In this study, we present a measurement of the W-boson-pair production cross section in pp¯ collisions at 1.96 TeV center-of-mass energy and the first measurement of the differential cross section as a function of jet multiplicity and leading-jet energy. The W+W– cross section is measured in the final state comprising two charged leptons and neutrinos, where either charged lepton can be an electron or a muon. Using data collected by the CDF experiment corresponding to 9.7 fb–1 of integrated luminosity, a total of 3027 collision events consistent with W+W– production are observed with an estimated background contribution of 1790±190 events. The measured total cross section is ?(pp¯→W+W–) = 14.0 ± 0.6(stat)+1.2–1.0 (syst)±0.8 (lumi) pb, consistent with the standard model prediction.

Book Measurement of the W W Cross Section in Pp Collisions at sqrt s

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

Book Particle Size Measurements

Download or read book Particle Size Measurements written by Henk G. Merkus and published by Springer Science & Business Media. This book was released on 2009-01-07 with total page 535 pages. Available in PDF, EPUB and Kindle. Book excerpt: This book focuses on the practical aspects of particle size measurement: a major difference with existing books, which have a more theoretical approach. Of course, the emphasis still lies on the measurement techniques. For optimum application, their theoretical background is accompanied by quantitative quality aspects, limitations and problem identification. In addition the book covers the phenomena of sampling and dispersion of powders, either of which may be dominant in the overall analysis error. Moreover, there are chapters on the general aspects of quality for particle size analysis, quality management, reference materials and written standards, in- and on-line measurement, definitions and multilingual terminology, and on the statistics required for adequate interpretation of results. Importantly, a relation is made to product performance, both during processing as well as in final application. In view of its set-up, this book is well suited to support particle size measurement courses.