Direct measurement of leptonic coupling asymmetries with polarized Zs

The SLD collaboration Abe, K. ; Akagi, T. ; Allen, N.J. ; et al.
Phys.Rev.Lett. 79 (1997) 804-808, 1997.
Inspire Record 442260 DOI 10.17182/hepdata.19552

We present direct measurements of the $Z~0$-lepton coupling asymmetry parameters, $A_e$, $A_\mu$, and $A_\tau$, based on a data sample of 12,063 leptonic $Z~0$ decays collected by the SLD detector. The $Z$ bosons are produced in collisions of beams of polarized $e~-$ with unpolarized $e~+$ at the SLAC Linear Collider. The couplings are extracted from the measurement of the left-right and forward-backward asymmetries for each lepton species. The results are: $A_e=0.152 \pm 0.012 {(stat)} \pm 0.001 {(syst)}$, $A_\mu=0.102 \pm 0.034 \pm 0.002$, and $A_\tau=0.195 \pm 0.034 \pm 0.003$.

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First measurement of the transverse spin asymmetries of the deuteron in semi-inclusive deep inelastic scattering

The COMPASS collaboration Alexakhin, V.Yu. ; Alexandrov, Yu. ; Alexeev, G.D. ; et al.
Phys.Rev.Lett. 94 (2005) 202002, 2005.
Inspire Record 677550 DOI 10.17182/hepdata.48553

First measurements of the Collins and Sivers asymmetries of charged hadrons produced in deep-inelastic scattering of muons on a transversely polarized 6-LiD target are presented. The data were taken in 2002 with the COMPASS spectrometer using the muon beam of the CERN SPS at 160 GeV/c. The Collins asymmetry turns out to be compatible with zero, as does the measured Sivers asymmetry within the present statistical errors.

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Azimuthal Correlations of Identical Pions in Pion - Nucleus and Pion - Nucleon Interactions at $p=40$-{GeV}/$c$

Grishin, V.G. ; Jenik, L. ; Kanarek, T. ;
Sov.J.Nucl.Phys. 34 (1981) 223, 1981.
Inspire Record 156944 DOI 10.17182/hepdata.39234
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A New measurement of the Collins and Sivers asymmetries on a transversely polarised deuteron target

The COMPASS collaboration Ageev, E.S. ; Alexakhin, V.Yu. ; Alexandrov, Yu. ; et al.
Nucl.Phys. B765 (2007) 31-70, 2007.
Inspire Record 729695 DOI 10.17182/hepdata.48535

New high precision measurements of the Collins and Sivers asymmetries of charged hadrons produced in deep-inelastic scattering of muons on a transversely polarised 6LiD target are presented. The data were taken in 2003 and 2004 with the COMPASS spectrometer using the muon beam of the CERN SPS at 160 GeV/c. Both the Collins and Sivers asymmetries turn out to be compatible with zero, within the present statistical errors, which are more than a factor of 2 smaller than those of the published COMPASS results from the 2002 data. The final results from the 2002, 2003 and 2004 runs are compared with naive expectations and with existing model calculations.

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Measurement of azimuthal hadron asymmetries in semi-inclusive deep inelastic scattering off unpolarised nucleons

The COMPASS collaboration Adolph, C. ; Akhunzyanov, R. ; Alekseev, M.G. ; et al.
Nucl.Phys. B886 (2014) 1046-1077, 2014.
Inspire Record 1278730 DOI 10.17182/hepdata.64754
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Measurement of the muon charge asymmetry in inclusive $pp \to W+X$ production at $\sqrt s =$ 7 TeV and an improved determination of light parton distribution functions

The CMS collaboration Chatrchyan, Serguei ; Khachatryan, Vardan ; Sirunyan, Albert M ; et al.
Phys.Rev. D90 (2014) 032004, 2014.
Inspire Record 1273570 DOI 10.17182/hepdata.65456

Measurements of the muon charge asymmetry in inclusive pp to WX production at sqrt(s) = 7 TeV are presented. The data sample corresponds to an integrated luminosity of 4.7 inverse femtobarns recorded with the CMS detector at the LHC. With a sample of more than twenty million W to mu nu events, the statistical precision is greatly improved in comparison to previous measurements. These new results provide additional constraints on the parton distribution functions of the proton in the range of the Bjorken scaling variable x from 10E-3 to 10E-1. These measurements and the recent CMS measurement of associated W + charm production are used together with the cross sections for inclusive deep inelastic ep scattering at HERA in a next-to-leading-order QCD analysis. The determination of the valence quark distributions is improved, and the strange-quark distribution is probed directly through the leading-order process g + s to W + c in proton-proton collisions at the LHC.

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Measurement of the muon charge asymmetry in $p\bar{p}$ $\to$ W+X $\to$ $\mu$$\nu$ + X events at $\sqrt{s}$=1.96  TeV

The D0 collaboration Abazov, Victor Mukhamedovich ; Abbott, Braden Keim ; Acharya, Bannanje Sripath ; et al.
Phys.Rev. D88 (2013) 091102, 2013.
Inspire Record 1253555 DOI 10.17182/hepdata.66280

We present a measurement of the muon charge asymmetry from the decay of the $W$ boson via W to mu nu using 7.3 fb^{-1} of integrated luminosity collected with the D0 detector at the Fermilab Tevatron Collider at sqrt{s} = 1.96 TeV. The muon charge asymmetry is presented in two kinematic regions in muon transverse momentum and event missing transverse energy: (p^{\mu}_{T} > 25 GeV, \met > 25 GeV) and (p^{\mu}_{T} > 35 GeV, \met > 35 GeV). The measured asymmetries are compared with theory predictions made using three parton distribution function sets. The predictions do not describe the data well for p^{\mu}_{T} > 35 GeV, \met > 35 GeV, and larger values of muon pseudorapidity.

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STUDY OF CORRELATIONS BETWEEN THE TRANSVERSE MOMENTA OF THE SECONDARY HADRONS IN anti-p p INTERACTIONS AT 32-GeV/c

Bogolyubsky, M.Yu. ; Borovikov, A.A. ; Bumazhnov, V.A. ; et al.
Sov.J.Nucl.Phys. 44 (1986) 631, 1986.
Inspire Record 223258 DOI 10.17182/hepdata.28957
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Spin correlation in $t\bar{t}$ production from $p\bar{p}$ collisions at $\sqrt{s} = 1.8$ TeV

The D0 collaboration Abbott, B. ; Abolins, M. ; Abramov, V. ; et al.
Phys.Rev.Lett. 85 (2000) 256-261, 2000.
Inspire Record 524260 DOI 10.17182/hepdata.42996

The D0 collaboration has performed a study of spin correlation in tt-bar production for the process tt-bar to bb-bar W^+W^-, where the W bosons decay to e-nu or mu-nu. A sample of six events was collected during an exposure of the D0 detector to an integrated luminosity of approximately 125 pb^-1 of sqrt{s}=1.8 TeV pp-bar collisions. The standard model (SM) predicts that the short lifetime of the top quark ensures the transmission of any spin information at production to the tt-bar decay products. The degree of spin correlation is characterized by a correlation coefficient k. We find that k>-0.25 at the 68% confidence level, in agreement with the SM prediction of k=0.88.

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Collins and Sivers asymmetries for pions and kaons in muon-deuteron DIS

The COMPASS collaboration Alekseev, M. ; Alexakhin, V.Yu. ; Alexandrov, Yu. ; et al.
Phys.Lett. B673 (2009) 127-135, 2009.
Inspire Record 779473 DOI 10.17182/hepdata.48532

The measurements of the Collins and Sivers asymmetries of identified hadrons produced in deep-inelastic scattering of 160 GeV/c muons on a transversely polarised 6LiD target at COMPASS are presented. The results for charged pions and charged and neutral kaons correspond to all data available, which were collected from 2002 to 2004. For all final state particles both the Collins and Sivers asymmetries turn out to be small, compatible with zero within the statistical errors, in line with the previously published results for not identified charged hadrons, and with the expected cancellation between the u- and d-quark contributions.

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Measurement of the inclusive leptonic asymmetry in top-quark pairs that decay to two charged leptons at CDF

The CDF collaboration Aaltonen, Timo Antero ; Amerio, Silvia ; Amidei, Dante E ; et al.
Phys.Rev.Lett. 113 (2014) 042001, 2014.
Inspire Record 1290358 DOI 10.17182/hepdata.64422
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Precise measurement of the e+ e- ---> mu+ mu- reaction at s**(1/2) = 57.77-GeV

The VENUS collaboration Miura, M. ; Odaka, S. ; Arima, T. ; et al.
Phys.Rev. D57 (1998) 5345-5362, 1998.
Inspire Record 452097 DOI 10.17182/hepdata.27142
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Final Results on $\mu$ and Tau Pair Production by the Jade Collaboration at {PETRA}

The JADE collaboration Hegner, S. ; Naroska, B. ; Schroth, F. ; et al.
Z.Phys. C46 (1990) 547-554, 1990.
Inspire Record 284560 DOI 10.17182/hepdata.15279
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Experimental limits on extra $Z$ bosons from $e^{+} e^{-}$ annihilation data with the VENUS detector at $\sqrt{s}$ = 50-GeV to approximately 64-GeV

The VENUS collaboration Abe, K. ; Amako, K. ; Arai, Y. ; et al.
Phys.Lett. B246 (1990) 297-305, 1990.
Inspire Record 296392 DOI 10.17182/hepdata.29664
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Analysis of Z0 couplings to charged leptons

The OPAL collaboration Akrawy, M.Z. ; Alexander, G. ; Allison, J. ; et al.
Phys.Lett. B247 (1990) 458-472, 1990.
Inspire Record 297139 DOI 10.17182/hepdata.29630
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Tests of the standard model and constraints on new physics from measurements of fermion pair production at 189-GeV to 209-GeV at LEP

The OPAL collaboration
Eur.Phys.J. C33 (2004) 173-212, 2004.
Inspire Record 628491 DOI 10.17182/hepdata.43174

Cross-section and angular distributions for hadronic and lepton-pair final states in e+e- collisions at centre-of-mass energies between 189 GeV and 209 GeV, measured with the OPAL detector at LEP, are presented and compared with the predictions of the Standard Model. The measurements are used to determine the electromagnetic coupling constant alphaem at LEP2 energies. In addition, the results are used together with OPAL measurements at 91-183 GeV within the S-matrix formalism to determine the gamma-Z interference term and to make an almost model-independent measurement of the Z mass. Limits on extensions to the Standard Model described by effective four-fermion contact interactions or the addition of a heavy Z boson are also presented.

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DELPHI results on the Z0 resonance parameters through its hadronic and leptonic decay modes

The DELPHI collaboration Abreu, P. ; Adam, W. ; Adami, F. ; et al.
Conference Paper, 1990.
Inspire Record 298840 DOI 10.17182/hepdata.47313
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Measurements of the line shape of the $Z^0$ and determination of electroweak parameters from its hadronic and leptonic decays

The DELPHI collaboration Abreu, P. ; Adam, W. ; Adye, T. ; et al.
Nucl.Phys. B417 (1994) 3-57, 1994.
Inspire Record 372144 DOI 10.17182/hepdata.48413
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Precise determination of the Z resonance parameters at LEP: 'Zedometry'

The OPAL collaboration
Eur.Phys.J. C19 (2001) 587-651, 2001.
Inspire Record 538108 DOI 10.17182/hepdata.49855

This final analysis of hadronic and leptonic cross-sections and of leptonic forward-backward asymmetries in e+e- collisions with the OPAL detector makes use of the full LEP1 data sample comprising 161 pb^-1 of integrated luminosity and 4.5 x 10^6 selected Z decays. An interpretation of the data in terms of contributions from pure Z exchange and from Z-gamma interference allows the parameters of the Z resonance to be determined in a model-independent way. Our results are in good agreement with lepton universality and consistent with the vector and axial-vector couplings predicted in the Standard Model. A fit to the complete dataset yields the fundamental Z resonance parameters: mZ = 91.1852 +- 0.0030 GeV, GZ = 2.4948 +- 0.0041 GeV, s0h = 41.501 +- 0.055 nb, Rl = 20.823 +- 0.044, and Afb0l = 0.0145 +- 0.0017. Transforming these parameters gives a measurement of the ratio between the decay width into invisible particles and the width to a single species of charged lepton, Ginv/Gl = 5.942 +- 0.027. Attributing the entire invisible width to neutrino decays and assuming the Standard Model couplings for neutrinos, this translates into a measurement of the effective number of light neutrino species, N_nu = 2.984 +- 0.013. Interpreting the data within the context of the Standard Model allows the mass of the top quark, mt = 162 +29-16 GeV, to be determined through its influence on radiative corrections. Alternatively, utilising the direct external measurement of mt as an additional constraint leads to a measurement of the strong coupling constant and the mass of the Higgs boson: alfa_s(mZ) = 0.127 +- 0.005 and mH = 390 +750-280 GeV.

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Interactions of 200-GeV/nucleon O-16 and S-32 ions in nuclear emulsions

Baroni, G. ; Bisi, V. ; Breslin, A.C. ; et al.
Nucl.Phys. A531 (1991) 691-708, 1991.
Inspire Record 313983 DOI 10.17182/hepdata.36711

This paper presents and contrasts features of the inelastic nuclear reactions of 200 GeV/nucleon 16 O and 32 S ions with emulsion nuclei. Both the multiplicities of shower particles and the extent of target fragmentation have been studied for varying degress of disruption of the projectile nuclei. The results may be interpreted within a simple geometrical model. In particular the rapidity distributions of those events which exhibit complete projectile break-up without any overt sign of low-energy target fragmentation have been determined. The interaction of secondary projectile fragments of charge two or more issuing from oxygen interactions were also studied and the mean free paths in emulsion of the primary 16 O and 32 S ions and all such fragments have been compared to those predicted by a simple Glauber model.

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Precision measurements of the neutral current from hadron and lepton production at LEP

The OPAL collaboration Acton, P.D. ; Alexander, G. ; Allison, John ; et al.
Z.Phys. C58 (1993) 219-238, 1993.
Inspire Record 352696 DOI 10.17182/hepdata.14495
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Measurement of electroweak parameters from hadronic and leptonic decays of the $Z^0$

The L3 collaboration Adeva, B. ; Adriani, O. ; Aguilar-Benitez, M. ; et al.
Z.Phys. C51 (1991) 179-204, 1991.
Inspire Record 314418 DOI 10.17182/hepdata.14940
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Measurement of the $Z^0$ line shape parameters and the electroweak couplings of charged leptons

The OPAL collaboration Alexander, G. ; Allison, John ; Allport, P.P. ; et al.
Z.Phys. C52 (1991) 175-208, 1991.
Inspire Record 315269 DOI 10.17182/hepdata.14859
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Study of the $e^+ e^-\to\mu^+ \mu^- \gamma$ reaction at center-of-mass energies between 54 and 64 GeV

The VENUS collaboration Yonezawa, Y. ; Abe, K. ; Amako, K. ; et al.
Phys.Lett. B264 (1991) 212-218, 1991.
Inspire Record 1389624 DOI 10.17182/hepdata.29359

The cross section and forward-backward muon charge asymmetry for the e + e − → μ + μ − γ reaction were measured to be σ =2.82±0.35 pb and A =−0.34±0.10 with the VENUS detector at TRISTAN at 〈√ s 〉=59.2GeV for an integrated luminosity of 53.5 pb −1 . The measured cross section agrees with the theoretical prediction. The asymmetry result is consistent with the electroweak prediction but not with the QED prediction at the level of 2 σ .

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Search for a $Z^\prime$ at the $Z$ resonance

The L3 collaboration Adriani, O. ; Aguilar-Benitez, M. ; Ahlen, S.P. ; et al.
Phys.Lett. B306 (1993) 187-196, 1993.
Inspire Record 355489 DOI 10.17182/hepdata.28919
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