Download or read book Results On alpha sub S and Tests of QCD From and Above the Z sup 0 written by and published by . This book was released on 2004 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: Measurements of[alpha][sub s] from e[sup+]e[sup -] annihilation experiments are reviewed and compared with measurements from other processes. Highlights are presented of recent QCD studies in e[sup+]e[sup -] annihilation at the Z[sup 0] resonance.

Download or read book Results on sub S and QCD from and Above the Z written by and published by . This book was released on 1997 with total page 28 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Results On alpha sub S and QCD from and Above the Z sup 0 written by and published by . This book was released on 2001 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: In electron-positron annihilation hadronic activity is, by construction, limited to the final state, making the study of hadronic events cleaner and simpler relative to lepton-hadron and hadron-hadron collisions, from both the experimental and theoretical points-of-view. To be specific, samples of hadronic events can be selected by experiments at the Z[sup 0] resonance with efficiency and purity of better than 99%. Jet and event-shape observables have been calculated at next-to-leading order, O([alpha][sub s][sup 2]), and some inclusive observables have been calculated at O([alpha][sub s][sup 3]). Non-perturbative calculations, in the form of power corrections to perturbatively-evaluated observables, have been performed, and there are well-understood models of hadronization that have been carefully tuned to the data collected over the past 20 years. Electron-positron annihilation thus provides an ideal environment for precise tests of QCD, and has yielded spectacular results. Here, measurements of[alpha][sub s] from e[sup+]e[sup[minus]] annihilation experiments are reviewed and compared with measurements from other processes. Highlights are presented of recent QCD studies in e[sup+]e[sup[minus]] annihilation at the Z[sup 0] resonance.

Download or read book Results on alpha sub S and QCD from and Above the Z written by and published by . This book was released on 1997 with total page 28 pages. Available in PDF, EPUB and Kindle. Book excerpt: In electron-positron annihilation hadronic activity is, by construction, limited to the final state, making the study of hadronic events cleaner and simpler relative to lepton-hadron and hadron-hadron collisions, from both the experimental and theoretical points-of-view. To be specific, samples of hadronic events can be selected by experiments at the Z° resonance with efficiency and purity of better than 99%. Jet and event-shape observables have been calculated at next-to-leading order, O([alpha]{sub s}2), and some inclusive observables have been calculated at O([alpha]{sub s}3). Non-perturbative calculations, in the form of power corrections to perturbatively-evaluated observables, have been performed, and there are well-understood models of hadronization that have been carefully tuned to the data collected over the past 20 years. Electron-positron annihilation thus provides an ideal environment for precise tests of QCD, and has yielded spectacular results. Here, measurements of [alpha]{sub s} from ee− annihilation experiments are reviewed and compared with measurements from other processes. Highlights are presented of recent QCD studies in ee− annihilation at the Z° resonance.

Download or read book Results on alpha s and QCD from and Above the Z0 written by Philip N. Burrows and published by . This book was released on 1997 with total page 56 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Scientific and Technical Aerospace Reports written by and published by . This book was released on 1995 with total page 538 pages. Available in PDF, EPUB and Kindle. Book excerpt: Lists citations with abstracts for aerospace related reports obtained from world wide sources and announces documents that have recently been entered into the NASA Scientific and Technical Information Database.

Download or read book Results On sub S and Tests of QCD From and Above the Z written by and published by . This book was released on 1997 with total page 28 pages. Available in PDF, EPUB and Kindle. Book excerpt: Measurements of?{sub s} from ee− annihilation experiments are reviewed and compared with measurements from other processes. Highlights are presented of recent QCD studies in e+e− annihilation at the Z° resonance.

Download or read book A Study of Energy energy Correlations and Measurement of alpha sub S at the Z sup 0 Resonance written by and published by . This book was released on 1992 with total page 20 pages. Available in PDF, EPUB and Kindle. Book excerpt: We present the energy-energy correlation (EEC) distribution and its asymmetry (AEEC) in hadronic decays of [Zeta][sup 0] bosons measured by the SLD at SLAC. The data are found to be in good agreement with the predictions of perturbative QCD and fragmentation Monte Carlo models of hadron production. After correction for hadronization effects the data are compared with [Omicron]([alpha][sub s][sup 2]) perturbative QCD calculations from various authors. Fits to the central region of the EEC yield substantially different values of the QCD scale [lambda][sub [ovr MS]] for each of the QCD calculations. There is also a sizeable dependence of the fitted [lambda][sub [ovr MS]] value on the QCD renormalization scale factor, f. Our preliminary results are [alpha][sub s](M [sub Z]) = 0.121 [plus minus] 0.002(stat.) [plus minus] 0.004(exp.sys.) [sub [minus]0.009][sup +0.016] (theor.) for EEC and [alpha][sub s](M[sub Z]) = 0.108 [plus minus] 0.003(stat.) [plus minus] 0.005(exp.sys.)[sub [minus]0.003][sup +0.008](theor.) for AEEC. The largest contribution to the error arises from the theoretical uncertainty in choosing the QCD renormalization scale.

Download or read book Department of Transportation Budget Program Analysis of Fiscal Year 1977 DOT Program by Policy and RD D Management Objectives Program Levels for Fiscal Years 1975 1976 1977 written by and published by . This book was released on 1976 with total page 212 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book A Study of Jet Rates and Measurement of alpha sub S at the Z sup 0 Resonance written by and published by . This book was released on 1993 with total page 156 pages. Available in PDF, EPUB and Kindle. Book excerpt: This experiment was performed with the SLD detector at the Stanford Linear Accelerator Center. Only charged tracks measured in the central drift chamber were used for the measurement of the jet production rates. The value of the strong coupling [alpha][sub s](M[sub Z][sup o]) is determined from the production rates of jets in hadronic Z[sup 0] decays in e[sup +] e[sup [minus]] annihilations. The relative jet rates are obtained using the JADE-type algorithms. The results are compared with the jet rates obtained from a new jet algorithm proposed by N. Brown et al. called the Durham'' algorithm. The data can be well described by O([alpha][sub s][sup 2]) QCD calculations and by QCD shower model calculations. A fit of the theoretical predictions to the data taken with the SLD yields a value, [alpha][sub s](M[sub Z][sup o]) = 0.120 [plus minus] 0.002(stat.) [plus minus] 0.003(exp.)[sub [minus]0.009][sup +0.011](theor.). The error is dominated by the theoretical uncertainties. The measurement is compared with results from other experiments and it is shown that the value obtained for [alpha][sub s] agrees well with these results and furthermore supports the evidence for the running of the strong coupling, consistent with the non-Abelian nature of QCD. The Stanford Linear Collider (SLC) can deliver partially longitudinally polarized electrons to the interaction point. Jet production rates and values for [alpha][sub s] are calculated both for right-handed and left-handed initial state electrons. All results are consistent with the unpolarized result, as predicted by the Standard Model.

Download or read book Government Reports Announcements Index written by and published by . This book was released on 1993 with total page 988 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book The Standard Model and Beyond written by Paul Langacker and published by CRC Press. This book was released on 2017-06-26 with total page 786 pages. Available in PDF, EPUB and Kindle. Book excerpt: This new edition of The Standard Model and Beyond presents an advanced introduction to the physics and formalism of the standard model and other non-abelian gauge theories. It provides a solid background for understanding supersymmetry, string theory, extra dimensions, dynamical symmetry breaking, and cosmology. In addition to updating all of the experimental and phenomenological results from the first edition, it contains a new chapter on collider physics; expanded discussions of Higgs, neutrino, and dark matter physics; and many new problems. The book first reviews calculational techniques in field theory and the status of quantum electrodynamics. It then focuses on global and local symmetries and the construction of non-abelian gauge theories. The structure and tests of quantum chromodynamics, collider physics, the electroweak interactions and theory, and the physics of neutrino mass and mixing are thoroughly explored. The final chapter discusses the motivations for extending the standard model and examines supersymmetry, extended gauge groups, and grand unification. Thoroughly covering gauge field theories, symmetries, and topics beyond the standard model, this text equips readers with the tools to understand the structure and phenomenological consequences of the standard model, to construct extensions, and to perform calculations at tree level. It establishes the necessary background for readers to carry out more advanced research in particle physics. Supplementary materials are provided on the author’s website and a solutions manual is available for qualifying instructors.

Download or read book LEP The Lord of the Collider Rings at CERN 1980 2000 written by Herwig Schopper and published by Springer Science & Business Media. This book was released on 2009-08-12 with total page 215 pages. Available in PDF, EPUB and Kindle. Book excerpt: Housed by a 4 m diameter tunnel of 27 km circumference, with huge underground labs and numerous surface facilities, and set up with a precision of 0.1 mm per kilometer, the Large Electron-Positron Collider (LEP) was not only the largest but also one of the most sophisticated scientific research instruments ever created by Man. Located at CERN, near Geneva, LEP was built during the years 1983 - 1989, was operational until 2000, and corroborated the standard model of particle physics through continuous high precision measurements. The Author, director-general of CERN during the crucial period of the construction of LEP, recounts vividly the convoluted decision-making and technical implementation processes - the tunnel alone being a highly challenging geo- and civil engineering project - and the subsequent extremely fruitful period of scientific research. Finally he describes the difficult decision to close down LEP, at a time when the discovery of the Higgs boson seemed within reach. LEP was eventually dismantled in 2000, enabling the tunnel to be reused for building the next generation machine, the much more powerful Large Hadron Collider (LHC), an upgrade then called LEP3 and foreseen from the beginning. It became operational just as this account was being completed. Written by the main protagonist responsible for making LEP a reality, this is the definitive inside story of a remarkable machine and the many thousands of scientists and engineers from around the world, whose efforts contributed to the new knowledge it produced.

Download or read book Deep Inelastic Scattering written by Masahiro Kuze and published by World Scientific. This book was released on 2007 with total page 996 pages. Available in PDF, EPUB and Kindle. Book excerpt: These proceedings present the most up-to-date status of deep inelastic scattering (DIS) physics. Topics such as structure function measurements and phenomenology, quantum chromodynamics (QCD) studies in DIS and photoproduction, spin physics and diffractive interactions are reviewed in detail, with emphasis on those studies that push the test of QCD and the Standard Model to the limits of their present range of validity, towards both the very high and the very low four-momentum transfers in leptonproton scattering.

Download or read book Government Reports Announcements Index written by and published by . This book was released on 1988 with total page 1132 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Cities and Their Vital Systems written by Advisory Committee on Technology and Society and published by National Academies Press. This book was released on 1989 with total page 1298 pages. Available in PDF, EPUB and Kindle. Book excerpt: Cities and Their Vital Systems asks basic questions about the longevity, utility, and nature of urban infrastructures; analyzes how they grow, interact, and change; and asks how, when, and at what cost they should be replaced. Among the topics discussed are problems arising from increasing air travel and airport congestion; the adequacy of water supplies and waste treatment; the impact of new technologies on construction; urban real estate values; and the field of "telematics," the combination of computers and telecommunications that makes money machines and national newspapers possible.

Download or read book Power Of Alpha The Electron Elementary Particle Generation With Alpha quantized Lifetimes And Masses written by Malcolm H Mac Gregor and published by World Scientific. This book was released on 2007-03-12 with total page 459 pages. Available in PDF, EPUB and Kindle. Book excerpt: This book is centered on the most pressing unsolved problem in elementary particle physics — the mass generation of particles. It contains physics that is not included in the Standard Model as it is now formulated, while at the same time being in conformity with the major results of the Standard Model, i.e. isotopic spins and interactions. It differs from the Standard Model in the treatment of masses and pseudoscalar mesons, and in the role assigned to the coupling constant α. Presented in a careful and phenomenological way, the material can easily be followed by all physicists, both experimental and theoretical, and also by interested workers in other fields. The author's website — 70mev.org — gives additional information about the applications of the constant α in particle physics.