Download or read book Determination of Alpha sub S from Energy energy Correlations in Ee Annihilation at 29 GeV written by and published by . This book was released on 1987 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: We have studied the energy-energy correlation in ee− annihilation into hadrons at .sqrt.s = 29 GeV using the Mark II detector at PEP. We find to O(.cap alpha./sub s/2) that .cap alpha./sub s/ = 0.158 +- 003 +- 008 if hadronization is described by string fragmentation. Independent fragmentation schemes give .cap alpha./sub s/ = .10 - 14, and give poor agreement with the data. A leading-log shower fragmentation model is found to describe the data well.
Download or read book Determination of alpha s from Energy energy Correlations in E E Annihilation at 29 GeV written by Darien Robert Wood and published by . This book was released on 1987 with total page 172 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Measurement of alpha s from Energy energy Correlations in Ee Annihilation at 29 GeV written by Hsiao-Ying Chao and published by . This book was released on 1990 with total page 164 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Determination of Alpha written by and published by . This book was released on 1987 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: We have studied the energy-energy correlation in ee− annihilation into hadrons at .sqrt.s = 29 GeV using the Mark II detector at PEP. We find to O(.cap alpha./sub s/2) that .cap alpha./sub s/ = 0.158 +- 003 +- 008 if hadronization is described by string fragmentation. Independent fragmentation schemes give .cap alpha./sub s/ = .10 - 14, and give poor agreement with the data. A leading-log shower fragmentation model is found to describe the data well.
Download or read book Measurement of alpha sub S in E sup e sup minus Annihilation at E sub Cm written by and published by . This book was released on 2005 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: A measurement of the strong coupling constant [alpha][sub s] using the event-shape variable y[sub 3] (the differential two-jet rate) in the reaction e[sup +]e[sup [minus]] [yields] hadrons is presented. The analysis is based on data from the TPC/Two-Gamma detector at the PEP e[sup +]e[sup [minus]] storage ring taken between 1984 and 1986 at a center-of-mass energy of E[sub cm] = 29 GeV. A value of [alpha][sub s](29 GeV) = 0.160 [+-] 0.012 is obtained, where the error is the quadratic sum of experimental and theoretical uncertainties. The procedure for determining [alpha][sub s] is the same as that used by the ALEPH and TOPAZ experiments, which allows for a consistent comparison of the [alpha][sub s] values obtained at different center-of-mass energies. The observed energy dependence [open-quotes]running[close-quotes] of [alpha][sub s] is found to be in good agreement with the QCD prediction, and is clearly incompatible with a constant value.
Download or read book Determination of alpha sub S M sub Z 2 from Hadronic Event Shape Observables in Ee Annihilation written by and published by . This book was released on 1996 with total page 11 pages. Available in PDF, EPUB and Kindle. Book excerpt: One of the most important tasks in high energy physics is the precise determination of the strong coupling [alpha]{sub s}(M{sub Z}2). Not only does measurement of [alpha]{sub s}(M{sub Z}2) in different hard processes and at different hard scales Q provide a fundamental test of the theory of strong interactions, Quantum Chromodynamics (QCD), but it also allows constraints on extensions to the Standard Model of elementary particles. Here, the determination of [alpha]{sub s}(M{sub Z}2) using O([alpha]{sub s}2) calculations of hadronic event shape observables in ee− annihilation is reviewed. The large scatter among [alpha]{sub s}(M{sub Z}2) values determined from different observables may be interpreted as arising from the effect of uncalculated higher-order contributions. The application of optimized perturbation theory and Pade approximants in an attempt to reduce this effect is discussed.
Download or read book Determination Of Alpha Sub S from a Differential Jet Multiplicity Distribution at SLC and PEP written by and published by . This book was released on 1990 with total page 7 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book DETERMINATION OF ALPHA S USING ENERGY ENERGY CORRELATION ASYMMETRY AND JET MASS DIFFERENCE AT MARK II SLC STRONG COUPLING CONSTANT ALPHA S written by MOKHTAR ABDALLAH CHMEISSANI and published by . This book was released on 1991 with total page 123 pages. Available in PDF, EPUB and Kindle. Book excerpt: The determination of the strong coupling constant $\alpha\sb s$, using Energy-Energy Correlation Asymmetry and jet mass difference with Mark II data at SLC (91 GeV) is presented.
Download or read book An 0 alpha S 2 Calculation of Energy energy Correlation in E E Annihilation and Comparison with Experimental Data written by A. Ali and published by . This book was released on 1982 with total page 3 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Inclusive Distributions and Two Particle Correlations in E e Annihilation at 29 GeV Center of mass Energy written by Marjorie Shapiro and published by . This book was released on 1984 with total page 332 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Determination Of alpha sub S M sub Z sup 2 from Hadronic Event Shape Observables in E sup e sup minus Annihilation written by and published by . This book was released on 2001 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: One of the most important tasks in high energy physics is the precise determination of the strong coupling[alpha][sub s](M[sub Z][sup 2]). Not only does measurement of[alpha][sub s](M[sub Z][sup 2]) in different hard processes and at different hard scales Q provide a fundamental test of the theory of strong interactions, Quantum Chromodynamics (QCD), but it also allows constraints on extensions to the Standard Model of elementary particles. Here, the determination of[alpha][sub s](M[sub Z][sup 2]) using O([alpha][sub s][sup 2]) calculations of hadronic event shape observables in e[sup+]e[sup[minus]] annihilation is reviewed. The large scatter among[alpha][sub s](M[sub Z][sup 2]) values determined from different observables may be interpreted as arising from the effect of uncalculated higher-order contributions. The application of optimized perturbation theory and Pade approximants in an attempt to reduce this effect is discussed.
Download or read book Inclusive Hadron Production and Two Particle Correlations in Ee Annihilation at 29 GeV Center of mass Energy written by and published by . This book was released on 1984 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: We have studied hadron production in ee− annihilation at 29 GeV center-of-mass energy using the PEP-4 Time Projection Chamber Detector. The inclusive cross sections and mean multiplicities for .pi./sup + -/, K/sup + -/ and (p + anti p) production have been measured using ionization energy loss to separate particle species. We find on average 10.7 +- 0.6 .pi./sup + -/, 1.35 +- 13 K/sup + -/ and 0.60 +- 0.08 (p + anti p) per multihadron event. The differential cross section is well described by a number of Monte Carlo hadronization models. In addition, we have observed correlations in rapidity space for identified pions and kaons. Short-range KK correlations provide evidence for local flavor compensation during hadronization. Long-range .pi pi. and KK correlations indicate that the initial partons carry flavor. We also observe significant long-range .pi. K correlations as a result of heavy quark decays. 85 references, 67 figures, 11 tables.
Download or read book Nuclear Science Abstracts written by and published by . This book was released on 1970-05 with total page 890 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Strong Interactions and Gauge Theories written by J. Thanh Van Tran and published by Atlantica Séguier Frontières. This book was released on 1986 with total page 706 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Search for Single photon Production in Ee Annihilation at 29 GeV Center of mass Energy written by Christopher Hearty and published by . This book was released on 1987 with total page 174 pages. Available in PDF, EPUB and Kindle. Book excerpt:
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 Measurement of alpha sub S in Ee Annihilation at E sub Cm written by and published by . This book was released on 1994 with total page 8 pages. Available in PDF, EPUB and Kindle. Book excerpt: A measurement of the strong coupling constant [alpha]{sub s} using the event-shape variable y3 (the differential two-jet rate) in the reaction ee− 2!hadrons is presented. The analysis is based on data from the TPC/Two-Gamma detector at the PEP e+e− storage ring taken between 1984 and 1986 at a center-of-mass energy of E{sub cm} = 29 GeV. A value of [alpha]{sub s}(29 GeV) = 0.160 ± 0.012 is obtained, where the error is the quadratic sum of experimental and theoretical uncertainties. The procedure for determining [alpha]{sub s} is the same as that used by the ALEPH and TOPAZ experiments, which allows for a consistent comparison of the [alpha]{sub s} values obtained at different center-of-mass energies. The observed energy dependence {open_quotes}running{close_quotes} of [alpha]{sub s} is found to be in good agreement with the QCD prediction, and is clearly incompatible with a constant value.
