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A new measurement of the W boson mass at D-Zero

Description: We present a new measurement of the W mass using the W {yields} e{nu} data from the D0 forward detectors at the Fermilab Tevatron p{anti p} Collider. This is the first measurement of the W mass with electron candidates in the range 1.5 <| {eta} |< 2.5. We present measurements of the W mass using the transverse mass, the electron transverse momentum and the neutrino transverse momen- tum, and the combined result using all three techniques. The combination of the forward detector measurement with the previous measurements using the central detector gives a new precise measurement of the W mass from D0.
Date: July 26, 1999
Creator: al., B. Abbott et
Partner: UNT Libraries Government Documents Department

The measuremnt of the mass of the W boson from the Tevatron

Description: This paper presents measurements of the mass of the W vector boson from the CDF and D0 experiments using data collected at {radical}s = 1.8 TeV during the 1994- 1995 data taking run. CDF finds a preliminary mass of M{sub W} = 80.43 {+-} 0.16 GeV and D0 measures a mass of M{sub W} = 80.44 {+-} 0.12 GeV.
Date: August 1, 1998
Creator: Thurman-Keup, R., CDF Collaboration
Partner: UNT Libraries Government Documents Department

The mass and width of the W boson

Description: The Tevatron and LEP2 experiments presently provide the most precise direct determinations of the mass and width of the W boson. The combined results are: M{sub w} = 80.394 {+-} 0.042 GeV and {Gamma}{sub w} = 2.095 {+-} 0.106 GeV. The results are in excellent agreement with the predictions of the Standard Model. In this article the latest results are described and the systematic errors which could limit further significant improvements in the precision of these measurements are reviewed.
Date: February 9, 2000
Creator: Lancaster, M.
Partner: UNT Libraries Government Documents Department

W and Z properties at the Tevatron

Description: The authors present recent results from CDF and D0 on W and Z production cross sections, the width of the W boson, {tau}-e universality in W decays, trilinear gauge boson couplings, and on the observation of Z {r{underscore}arrow} b{anti b}.
Date: January 26, 2000
Creator: Ellison, J.
Partner: UNT Libraries Government Documents Department

Measurement of the W Boson Production Asymmetry and W Boson Width at CDF

Description: We describe two measurements using 110 {+-} 7 pb{sup -1} of data collected by the CDF detector during 1992-95. The first is a new measurement of the charge asymmetry in the lepton rapidity range 0 < {vert_bar}y{sub l}{vert_bar} < 2.5 using W {yields} {mu}{nu}, e{nu} events. The asymmetry data constrain the ratio of d and u quark momentum distributions in the proton over the x range of 0.006 to 0.34 at Q{sup 2} {approx} M{sub W}{sup 2}. Although the data in the central rapidity region ({vert_bar}y{sub l}{vert_bar} < 1.1) are reproduced by modern parametrizations of parton distributions, there are differences in the high rapidity regions. The second measurement is a direct measurement of the W width using the lineshape of the transverse mass spectrum. The extracted W width is in good agreement with the standard model value, and with values obtained from the indirect method using the measured ratio of W and Z events.
Date: May 1, 1998
Creator: Bodek, A.
Partner: UNT Libraries Government Documents Department

Structure functions of electroweak boson and leptons

Description: The QCD structure of the electroweak bosons is reviewed and the lepton structure function is defined and calculated. The leading order splitting functions of electron into quarks are extracted, showing an important contribution from {gamma}-Z interference. Leading logarithmic QCD evolution equations are constructed and solved in the asymptotic region where log{sup 2} behavior of the Parton densities is observed. Possible applications with clear manifestation of ``resolved`` photon and weak bosons are discussed. 8 refs., 3 figs.
Date: April 2, 1996
Creator: Slominski, W & Szwed, J.
Partner: UNT Libraries Government Documents Department

Results on hard diffraction from CDF

Description: Results on diffractive W-boson and dijet production, selected with a rapidity gap in the forward detector region, are briefly summarized. The new sample of Run 1C data with a Roman Pot trigger has been analyzed for dijet production in single diffraction and double pomeron exchange. Comparisons of diffractive to non-diffractive dijet events are presented.
Date: May 1, 1998
Creator: Borras, K.
Partner: UNT Libraries Government Documents Department

Measurement of R{sub 10} ({sigma}(W+ > or = to 1 Jet)/{sigma}(W)) at CDF

Description: We present a measurement of the (W + {>=} 1 Jet)/(W Inclusive) cross section ratio, R{sub 10} , in W {yields} e{nu} events for jet ET thresholds ranging from 15 to 95 GeV. Using roughly 100 pb{sup -1} data from the {radical}s = 1.8 TeV p{anti p} collisions at the Fermilab Tevatron Collider, we compare the measured values of R{sub 10} to LO and NLO QCD predictions. Comparisons are made for both 0.4 and 0.7 jet cone clustering. Good agreement between data and theory is observed over a large range of jet E{sub T} thresholds for both cone sizes.
Date: October 1, 1998
Creator: Flaugher, Brenda
Partner: UNT Libraries Government Documents Department

New W mass results from CDF and D0

Description: This article describes recent measurements of the W mass by the CDF and D0 Collabo-rations. CDF obtains a preliminary result of 80.473 ± 0.113 GeV for the W mass in the electron channel and D0 reports a preliminary result of 80.766 ± 0.234 GeV for electrons in the more forward (Endcap) rapidities. When combined with all previous measurements, the current average for the W mass measured at the Tevatron is 80.450 ± 0.063 GeV.
Date: October 25, 1999
Creator: Carithers, Bill
Partner: UNT Libraries Government Documents Department

A new measurement of the W mass

Description: The CDF collaboration has measured the mass of the W boson using 5718 W {yields} e{nu} and 3268 W {yields} {mu}{nu} events collected in {approximately} 20 pb{sup {minus}1} in Run Ia at the Fermilab Tevatron. The measurement yields M{sub W} = 80.41 {+-} 0.18 GeV/c{sup 2}.
Date: May 1, 1995
Creator: Frisch, H.J.
Partner: UNT Libraries Government Documents Department

Direct and indirect measurements of the W boson mass at Fermilab

Description: Presented are the direct measurements of the W boson mass from the CDF and D0 experiments at the Fermilab p{bar p} collider using data from the 1994--1995 run. The W from the D0 experiment is 80.44 {+-} 0.12 GeV and the preliminary mass from CDF is 80.43 {+-} 0.16 GeV. Combining these mass values with the previous Tevatron measurements leads to a M{sub W} 80.41 {+-} 0.09 GeV. Also, presented is the new measurement of sin{sup 2} {Theta}{sub W}{sup on-shell} = 0.2199 {+-} 0.0020(stat) {+-} 0.0009(syst) from the deep inelastic neutrino scattering experiment (NuTeV) at Fermilab. In the context of the Standard Model this can be interpreted as a M{sub W} = 80.53 {+-} 0.11 GeV.
Date: June 1, 1998
Creator: Flattum, E.
Partner: UNT Libraries Government Documents Department

High energy photon-neutrino interactions

Description: A general decomposition of the amplitudes for the 2 {r_arrow} 2 processes {gamma}{nu} {r_arrow} {gamma}{nu} and {gamma}{gamma} {r_arrow} {nu}{bar {nu}} is obtained using gauge invariance and Bose symmetry. The restrictions implied by this decomposition are investigated for the reaction {gamma}{gamma} {r_arrow} {nu}{bar {nu}} by computing the one-loop helicity amplitudes in the standard model. In the center of mass, where {radical}s = 2{omega}, the cross section grows roughly as {omega}{sup 6} up to the threshold for W-boson production, {radical}s = 2m{sub W}. Astrophysical implications of very high energy photon-neutrino interactions are discussed.
Date: July 14, 1998
Creator: Abbasabadi, A.; Devoto, A.; Dicus, D.A. & Repko, W.W.
Partner: UNT Libraries Government Documents Department

Top quark results from the Tevatron Collider Experiments

Description: The authors present the latest results about the top quark obtained at the Fermilab Tevatron Collider by the CDF and D0 experiments. Production cross section and mass measurements are briefly summarized. They report on studies of the top P{sub T} distribution in t{anti t} production and of the mass of the t{anti t} system. Properties on the top decay are reviewed: {Lambda}(t{r_arrow}Wb)/{Lambda}(t{r_arrow}Wq), helicity of the W's from top decay and correlations of decay products. Finally, new results on searches for electroweak production of single top are reported.
Date: June 7, 2000
Creator: Leone, Sandra
Partner: UNT Libraries Government Documents Department

Bose-Einstein correlations in e{sup +}e{sup {minus}} {r_arrow} W{sup +}W{sup {minus}} at a linear collider

Description: The authors show that the most popular method to simulate Bose-Einstein (BE) interference effects predicts negligible correlations between identical pions originating from the hadronic decay of different W's produced in e{sup +}e{sup {minus}} {r_arrow} W{sup +}W{sup {minus}} {r_arrow} 4 jets at typical linear collider energies.
Date: March 3, 2000
Creator: Chekanov, S. V.; De Roeck, A. & De Wolf, E. A.
Partner: UNT Libraries Government Documents Department

Rapidity gaps and hard diffraction at the Tevatron

Description: Preliminary results on jet production with rapidity gaps in p{anti p} collisions are presented for both D0 and CDF. An excess of events with a forward rapidity gap is observed at both {radical}s=1800 GeV and 630 GeV, consistent with a hard single diffractive process. The first evidence for diffractive W production is presented. A class of events with two forward gaps and central dijets is observed at {radical}s=1800 GeV, a topology that is consistent with hard double pomeron exchange. Kinematic properties of events containing rapidity gaps are measured.
Date: June 1, 1997
Creator: Abbott, B. & Collaborations, CDF and D0
Partner: UNT Libraries Government Documents Department

WW and WZ production at the tevatron

Description: Direct limits are set on WWZ and WW{gamma} three-boson couplings in a search for WW and WZ production in p{bar p} collisions at {radical}s = 1.8 TeV using the D(0) and CDF detectors at the Fermilab Tevatron.
Date: April 1, 1995
Creator: Fuess, T.A.
Partner: UNT Libraries Government Documents Department

Vector boson p{sub T} measurements

Description: The current experimental status of vector boson p{sub T} measurements is reviewed. The recent Monte-Carlo implementations of vector boson p{sub T} distributions are compared to the data and the issues involved in making a meaningful comparison are outlined. The method used by CDF to obtain a W p{sub T} distribution from the measured Z p{sub T} distribution is also described.
Date: January 26, 2000
Creator: Lancaster, M. & Waters, D.S.
Partner: UNT Libraries Government Documents Department

Measurement of the W boson mass from CDF

Description: The CDF collaboration has measured the mass of the W boson to be M{sub W} = 80.41 {plus_minus} 0.18 GeV/c{sup 2} using 5718 W {yields} e{nu} events and 3268 W {yields} {mu}{nu} events collected in {approximately} 19 pb{sup {minus}1} from the 1992--93 collider run at the Fermilab Tevatron. This measurement has an uncertainty half that of the best previously published measurements.
Date: July 1995
Creator: Kim, Young-Kee
Partner: UNT Libraries Government Documents Department

Precision measurement of sin(squared) {theta}{sub W} from {nu}-N scattering at NuTeV and direct measurements of M{sub W}

Description: We present the preliminary result of sin{sup 2}{theta}{sub W} from {nu}-N deep inelastic scattering experiment, NuTeV, at Fermilab. This measurement of sin{sup 2}{theta}{sub W} comes from measuring the Paschos-Wolfenstein parameter R=({sigma}{sup {nu}}{sub NC}-{sigma}{sup {anti {nu}}}{sub NC}), using separate beams of {nu} and {anti {nu}}, utilizing the SSQT. The resulting value of sin{sup 2}{theta}{sub W}{sup on-shell} is 0.2253 {+-} 0.0019(stat) {+-} 0.0010(syst). This value is equivalent to the mass of the W boson, M{sub W} = 80.26 {+-} 0.11 GeV/c{sup 2}. We also summarize the direct measurements of M{sub W} from the Tevatron {anti p}p collider experiments, D0 and CDF. Combining these two direct measurements yields M{sub W} = 80.37 {+-} 0.08 GeV/c{sup 2}.
Date: August 1, 1998
Creator: Yu, J.
Partner: UNT Libraries Government Documents Department

Precision tests of quantum chromodynamics and the standard model

Description: The authors discuss three topics relevant to testing the Standard Model to high precision: commensurate scale relations, which relate observables to each other in perturbation theory without renormalization scale or scheme ambiguity, the relationship of compositeness to anomalous moments, and new methods for measuring the anomalous magnetic and quadrupole moments of the W and Z.
Date: June 1, 1995
Creator: Brodsky, S. J. & Lu, H. J.
Partner: UNT Libraries Government Documents Department

A search for right-handed dW bosons in {bar p}p collisions with the D0 detector at Fermilab

Description: This thesis reports on a search for right-handed W bosons (W{sub R}). Data collected with the D0 detector at the Fermilab Tevatron p{ovr p} collider at {radical}s=1.8 TeV were used to search for W{sub R} decays into an electron and a massive right-handed neutrino W{sub R}{sup {+-}} {r_arrow} e{sup {+-}}N{sub R}. Using the inclusive electron data, mass limits independent of the N{sub R} decay were set: m{sub W{sub R}} > 650 GeV/c{sup 2} and m{sub W{sub R}} > 720 GeV/c{sup 2} at the 95% confidence level, valid for m{sub N{sub R}} < {1/2}m{sub W{sub R}} and m{sub N{sub R}} {much_lt} m{sub W{sub R}} respectively (assuming Standard Model couplings). The latter also represents a new lower limit on the mass of a heavy left-handed W boson (W{prime}) decaying into e{nu}. In addition, limits on m{sub W{sub R}} valid for larger values of the N{sub R} mass were obtained assuming that N{sub R} decays to an electron and two jets. 50 refs., 58 figs., 14 tabs.
Date: January 1, 1996
Creator: Goldschmidt, A.
Partner: UNT Libraries Government Documents Department

Tests of proton structure functions using leptons at CDF and D0: W charge asymmetry and Drell-Yan production. Version 1.0

Description: High statistics W charge asymmetry measurements at the Tevatron {bar p}p collider significantly constrain the u and d quark distributions, and specifically the slope of the d(x)/u(x) in the x range 0.007 to 0.27. The authors present measurements of lepton charge asymmetry as a function of lepton rapidity, A(y{sub l}) at {radical}s = 1.8 TeV for {vert_bar}y{sub l}{vert_bar} < 2.0, for the W decays to electrons and muons recorded by the CDF detector during the 1992-93 run ({approx} 20 pb{sup {minus}1}), and the first {approx} 50 pb{sup {minus}1} of data from the 1994-95 run. These precise data make possible further discrimination between sets of modern parton distributions. In particular it is found that the most recent parton distributions, which included the CDF 1992-93 W asymmetry data in their fits (MRSA, CTEQ3M and GRV94) are still in good agreement with the more precise data from the 1994-95 run. W charge asymmetry results from D0 based on {approx} 6.5 pb{sup {minus}1} data from 1992-1993 run and {approx} 29.7 pb{sup {minus}1} data from 1994-1995 run, using the W decays to muons, are also presented and are found to be consistent with CDF results. In addition, the authors present preliminary measurement of the Drell-Yan cross-section by CDF using a dielectron sample collected during the 1993-94 run ({approx} 20 pb{sup {minus}1}) and a high mass dimuon sample from the combined 1993-94 and 1994-95 runs ({approx} 70 pb{sup {minus}1}). The measurement is in good agreement with predictions using the most recent PDFs in a dilepton mass range between 11 and 350 GeV/c{sup 2}.
Date: June 13, 1995
Creator: de Barbaro, P.
Partner: UNT Libraries Government Documents Department

The polarization asymmetry in {gamma}e collisions at the NLC and triple gauge Boson couplings

Description: The capability of the NLC in the {gamma}e collider mode to probe the CP-conserving {gamma}WW and {gamma}ZZ anomalous couplings through the use of the polarization asymmetry is examined. When combined with other measurements, very strong constraints on both varieties of anomalous couplings can be obtained. The author shows that these bounds are complementary to those that can be extracted from data taken at the LHC.
Date: September 1, 1996
Creator: Rizzo, T.G.
Partner: UNT Libraries Government Documents Department

Sea and gluon spin structure function measurements at RHIC

Description: The first polarized collider where one collides 250-GeV/c beams of 70% polarized protons at high luminosity is under construction. This will allow a determination of the nucleon spin-dependent structure functions over a large range in x and a collection of sufficient W and Z events to investigate extremely interesting spin-related phenomena.
Date: February 1, 1995
Creator: Yokosawa, A.
Partner: UNT Libraries Government Documents Department