Download or read book A Measurement of the Partial Width of the Z Boson Into B Quarks and the Forward backward Asymmetry in the Reaction E E Z Bb Using Inclusive Electrons written by Paul Robert Schenk and published by . This book was released on 1992 with total page 286 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book A Measurement of the Partial Width of the Z0 Boson Into B Quarks and the Forward backward Asymmetry in the Reaction Ee Z0 Bb Using Inclusive Electrons written by Paul Robert Schenk and published by . This book was released on 1992 with total page 0 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book A Measurement of the B quark Forward backward Charge Asymmetry in Electron positron Annihilation at a Center of mass Energy of 58 GeV written by Timothy Lester Thomas and published by . This book was released on 1995 with total page 548 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Z Boson Asymmetry Measurements at the Tevatron written by and published by . This book was released on 2014 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: We present measurements of the forward-backward asymmetry (A_fb) in dilepton pair decays of Z bosons produced in ppbar collisions using the full Tevatron dataset. The CDF experiment extracts a value for the effective weak mixing angle parameter sin^{2}\theta^{l}_{eff} of 0.2315 +/- 0.0010 from the A_fb distribution of dimuon events in 9.2 fb^{-1} of integrated luminosity. From dielectron events in 9.7 fb^{-1} of data, the D0 experiment finds sin^{2}\theta^{l}_{eff} = 0.23106 +/- 0.00053, the world's most precise measurement of sin^{2}\theta^{l}_{eff} from hadron colliders and with light quark couplings.

Download or read book Measurement of the Z Boson Branching Fraction Into Hadrons Containing Bottom Quarks written by J. Frederic Kral and published by . This book was released on 1990 with total page 286 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book The Left right Forward backward Asymmetry of Heavy Quarks Measured with Jet Charge and with Leptons at the SLD written by and published by . This book was released on 1994 with total page 7 pages. Available in PDF, EPUB and Kindle. Book excerpt: The authors present direct measurements of the left-right asymmetry of b- and c-quarks from the decay of Z° bosons produced in the annihilation of longitudinally polarized electrons and unpolarized positrons. Two complementary techniques are presented: (1) Z° --> b{bar b} decays are tagged using track impact parameters with b{bar b} discrimination provided by momentum-weighted track charge; (2) semileptonic b-decays are tagged using high p and p{sub T} muons and electrons. The preliminary results from their 1993 data sample are: A{sub b} = 0.93 " 0.13 " 0.13 for the jet charge and A{sub b} = 0.93 " 0.14 " 0.09, and A{sub c} = 0.40 " 0.23 " 0.20 for the leptons, where the first error is statistical and the second systematic.

Download or read book Basics of Perturbative QCD written by Yuri Dokshitzer and published by Atlantica Séguier Frontières. This book was released on 1991 with total page 286 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Measurements of B quark Forward backward Charge Asymmetry and Axial vector Coupling Using Inclusive Muons in E e Annihilation at s written by and published by . This book was released on 1991 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Measurement of the Forward backward Asymmetry in E e bb and the B quark Branching Ratio to Muons at TRISTAN Using Neural Networks written by K. Ueno and published by . This book was released on 1996 with total page 18 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Measurement of the Polarized Forward backward Asymmetry of Z B bar B Using a Lifetime Tag and Momentum weighted Track Charge written by and published by . This book was released on 1995 with total page 6 pages. Available in PDF, EPUB and Kindle. Book excerpt: We present a direct measurement of the parity-violating parameter A{sub b} by analyzing the left-right forward-backward asymmetry of b quarks in ee− --> Z{sup o} --> b{bar b}. The SLD experiment observes hadronic decays of Z{sup o} bosons produced at resonance in collisions of longitudinally polarized electrons and unpolarized positrons at the SLC. Heavy flavor decays of the Z{sup o} are identified by taking advantage of the long lifetime of B hadrons, the small, stable SLC beam spot, and precise tracking from SLD. The asymmetry A{sub b} is measured with a self-calibrating technique employing momentum-weighted track charge from both hemispheres in the tagged events. From our 1994--1995 sample of 3.6 pb−1 of ee− annihilation data with a luminosity-weighted average e− polarization of 77.3%, and our 1993 sample of 1.8 pb−1 with a luminosity-weighted polarization of 63.1%, we obtain A{sub b}(preliminary) = 0.843 " 0.046(stat.) " 0.051(syst.).

Download or read book Measurement of the Polarized Forward Backward Asymmetry of Z0 Bb Using a Lifetime Tag and Momentum Weighted Track Charge written by and published by . This book was released on 2004 with total page 18 pages. Available in PDF, EPUB and Kindle. Book excerpt: We present a direct measurement of the parity violating parameter A{sub b} by analyzing the left right forward backward asymmetry of b quarks in ee− --> Z° --> b{bar b}. The SLD experiment observes hadronic decays of Z° bosons produced at resonance in collisions of longitudinally polarized electrons and unpolarized positrons at the SLC. Heavy flavor decays of the Z° are identified by using the topologically reconstructed mass of B hadrons. The asymmetry A{sub b} is measured with a self calibrating technique employing momentum weighted track charge from both hemispheres in the tagged events. From our 1994-1995 sample of 3.6 pb−1 of ee− annihilation data with a luminosity weighted average e− polarization of 77%, and our 1993 sample of 1.8 pb−1 with a luminosity-weighted polarization of 63%, we obtain A{sub b} = 0.911 " 0.045(stat.) " 0.045(syst.).

Download or read book The Left right Forward backward Asymmetry for B Quarks at the SLD written by and published by . This book was released on 1994 with total page 199 pages. Available in PDF, EPUB and Kindle. Book excerpt: The left-right asymmetry for b quarks, A{sub b}, is precisely predicted by the Weinberg-Salam-Glashow model of particle interactions, now the standard model for high-energy particle physics. As a test of this model, A{sub b} is directly measured at the SLC Large Detector (SLD) by taking advantage of the unique polarized electron beam at the Stanford Linear Collider (SLC) and measuring the left-right forward-backward asymmetry of b quarks. To measure the asymmetry, b quarks are identified using muons of high total and transverse momenta. The result for the 1993 data sample of 37,843 hadronic Z's is A{sub b} = 0.91 " 0.19 " 0.06, where the first error is statistical and the second systematic. This result is in agreement with the standard model prediction of A{sub b} = 0.935.

Download or read book MEASUREMENT of the Forward Backward Asymmetry in Z bb bar and Z cc bar Decays with Leptons Extras written by S. SCHAEL and published by . This book was released on 2001 with total page 0 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Left right Forward backward Asymmetry for C and B Quarks written by and published by . This book was released on 1995 with total page 3 pages. Available in PDF, EPUB and Kindle. Book excerpt: This report reviews preliminary direct measurements of A{sub b} and A{sub c} from a sample of 100,000 hadronic Z° decays accumulated during the 1994-1995 run with a luminosity-weighted average e− polarization {vert_bar}P{sub e}{vert_bar} ≈ 77.3 ± 0.6% combined with another 50,000 events from the 1993 run with {vert_bar}P{sub e}{vert_bar} = 63.0 ± 1.1%. The description of SLD detector components can be found in references of the individual analysis papers. All asymmetry measurement results described in this paper apply cos[theta]-dependent QCD corrections.

Download or read book Measurement of the Inclusive Forward Backward textbf textrm t bar textrm textbf t Production Asymmetry and Its Rapidity Dependence textrm textbf dA textrm textbf fb written by and published by . This book was released on 2010 with total page 140 pages. Available in PDF, EPUB and Kindle. Book excerpt: Early measurements of a large forward-background asymmetry at the CDF and D0 experiments at Fermilab have generated much recent interest, but were hampered by large uncertainties. We present here a new measurement of the parton level forward-backward asymmetry of pair-produced top quarks, using a high-statistics sample with much improved precision. We study the rapidity, y{sub top}, of the top quark production angle with respect to the incoming parton momentum in both the lab and t{bar t} rest frames. We find the parton-level forward-backward asymmetries to be A{sub fb}{sup p{bar p}} = 0.150 ± 0.050{sup stat} ± 0.024{sup syst} A{sub fb}{sup t{bar t}} = 0.158 ± 0.072{sup stat} ± 0.024{sup syst}. These results should be compared with the small p{bar p} frame charge asymmetry expected in QCD at NLO, A{sub fb} = 0.050 ± 0.015. Additionally, we introduce a measurement of the A{sub fb} rapidity dependence dA{sub fb}/d([Delta]y). We find this to be A{sub fb}{sup t{bar t}}).

Download or read book Extraction of the Width of the W Boson from a Measurement of the Ratio of the W and Z Cross Sections written by and published by . This book was released on 2001 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: This dissertation reports on measurements of inclusive cross sections times branching fractions into electrons for W and Z bosons produced in p[anti p] collisions at[radical]s= 1.8 TeV. From an integrated luminosity of 84.5 pb[sup[minus]1] recorded in 1994--1995 by the D0 detector at the Fermilab Tevatron[Lambda] the cross sections are measured to be[sigma]p[anti p][r-arrow] W+ X[center-dot] B(W[r-arrow] e[nu])= 2,310[+-] 10 (stat)[+-] 50 (Syst)[+-] 100 (lum) pb and[sigma](p[anti p][r-arrow] Z+ X)[center-dot] B(Z[r-arrow] ee)= 221[+-] 3 (stat)[+-] 4 (Syst)[+-] 10 (lum) pb. The cross section ratio R is determined to be[sigma](p[anti p][r-arrow] W+ X)[center-dot] B(W[r-arrow] e[nu])/[sigma](p[bar p][r-arrow] Z+ X)[center-dot] B(Z[r-arrow] ee)= 10.43[+-] 0.15 (stat)[+-] 0.20 (syst)[+-] 0.10 (NLO)[Lambda] and R is used to determine B(W[r-arrow] e[nu])= 0.1044[+-] 0.0015 (stat)[+-] 0.0020 (syst)[+-] 0.0017 (theory)[+-] 0.0010 (NLO)[Lambda] and[Lambda][sub W]= 2.169[+-] 0.031 (stat)[+-] 0.042 (syst)[+-] 0.041 (theory)[+-] 0.022 (NLO) GeV. The latter is used to set a 95% confidence level upper limit on the partial decay width of the W boson into non-standard model final states[Lambda][Lambda][sub W][sup inv][Lambda] of 0.213 GeV.

Download or read book Measurement of the Polarized Forward backward Asymmetry of B Quarks at SLD written by and published by . This book was released on 1997 with total page 134 pages. Available in PDF, EPUB and Kindle. Book excerpt: This thesis presents a direct measurement of the parity-violating parameter A{sub b} using the Left-Right Forward-Backward asymmetry of b{anti b} pair production at the Z° pole. The measurement was done at the Stanford Linear Accelerator Center (SLAC) using data from the SLAC Large Detector (SLD). The authors take advantage of the high polarization of the SLAC Linear Collider (SLC) electron beam. To identify heavy flavor decays of the Z°, they use a b-tag based on the topological reconstruction of the mass of the B vertex. Discrimination between the b and {anti b} quark directions is provided by a self-calibrating jet-charge technique. This technique allows calibration of the analyzing power from data and gives a much reduced model dependence. Based on the 1994--95 (1993) sample of 100,000 (50,000) Z° decays recorded with an electron beam polarization of P{sub e} = 77% (63%), they have obtained A{sub b} = 0.911 " 0.045(stat) " 0.045(syst). This value is in goo d agreement with the Standard Model.