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We report on a measurement of the mass of the Z 0 boson, its total width, and its partial decay widths into hadrons and leptons. On the basis of 25 801 hadronic decays and 1999 decays into electrons, muons or taus, selected over eleven energy points between 88.28 GeV and 95.04 GeV, we obtain from a combined fit to hadrons and leptons a mass of M z =91.154±0.021 (exp)±0.030 (LEP) GeV, and a total width of Γ z =2.536±0.045 GeV. The errors on M z have been separated into the experimental error and the uncertainty due to the LEP beam energy. The measured leptonic partial widths are Γ ee =81.2±2.6 MeV, Γ μμ =82.6± 5.8 MeV, and Γ ττ =85.7±7.1 MeV, consistent with lepton universality. From a fit assuming lepton universality we obtain Γ ℓ + ℓ − = 81.9±2.0 MeV. The hadronic partial width is Γ had =1838±46 MeV. From the measured total and partial widths a model independent value for the invisible width is calculated to be Γ inv =453±44 MeV. The errors quoted include both the statistical and the systematic uncertainties.

4 data tables

Table 1

Errors are statistical and point to point systematic luminosity error of 1 pct.

Table 2

Measured values of e+ e- --> e+ e- cross section.

Table 3

Corrected cross section. Corrections are for t-channel effects and loss of acollinear events near the boundary of the acceptance.

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W2 and Q2 dependence of charged hadron and pion multiplicities in neutrino p and anti-neutrino p charged current interactions

The WA21 collaboration Jones, G.T. ; Jones, R.W.L. ; Morrison, Douglas R.O. ; et al.

Z.Phys.C 46 (1990) 25-34, 1990.

Inspire Record 305244 DOI 10.17182/hepdata.1699

Using data onvp and$\bar vp$ charged current interactions from a bubble chamber experiment with BEBC at CERN, the average multiplicities of charged hadrons and pions are determined as functions ofW2 andQ2. The analysis is based on ∼20000 events with incidentv and ∼10000 events with incident$\bar v$. In addition to the known dependence of the average multiplicity onW2 a weak dependence onQ2 for fixed intervals ofW is observed. ForW>2 GeV andQ2>0.1 GeV2 the average multiplicity of charged hadrons is well described by〈n〉=a1+a2ln(W2/GeV2)+a3ln(Q2/GeV2) witha1=0.465±0.053,a2=1.211±0.021,a3=0.103±0.014 for thevp anda1=−0.372±0.073,a2=1.245±0.028,a3=0.093±0.015 for the$\bar vp$ reaction.

72 data tables

Table 1

No description provided.

Table 2

No description provided.

Table 3

No description provided.

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A High Statistics Measurement of the Deuteron Structure Functions F2 (X, $Q^2$) and R From Deep Inelastic Muon Scattering at High $Q^2$

The BCDMS collaboration Benvenuti, A.C. ; Bollini, D. ; Bruni, G. ; et al.

Phys.Lett.B 237 (1990) 592-598, 1990.

Inspire Record 285497 DOI 10.17182/hepdata.6191

We present results on a high statistics study of the nucleon structure functions F 2 ( x , Q 2 ) and R = σ L / σ T measured in deep inelastic scattering of muons on a deuterium target. The analysis is based on 8×10 5 events after all cuts, recorded at beam energies of 120, 200 and 280 GeV in the kinematic range 0.06⩽ × ⩽0.80 and 8GeV 2 ⩽ Q 2 ⩽260GeV 2 . Scaling violations observed in the data are in agreement with predictions of perturbative QCD and allow to determine the QCD mass scale parameter Λ.

87 data tables

Table 1

No description provided.

Table 2

R=SIG(L)/SIG(T) is taken to be zero.

Table 3

R=SIG(L)/SIG(T) is taken to be zero.

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A Precise Determination of the Number of Families With Light Neutrinos and of the $Z$ Boson Partial Widths

The ALEPH collaboration Decamp, D. ; Deschizeaux, B. ; Lees, J.P. ; et al.

Phys.Lett.B 235 (1990) 399-411, 1990.

Inspire Record 284411 DOI 10.17182/hepdata.29743

More extensive and precise results are reported on the parameters of Z decay. On the basis of 20 000 Z decays collected with the ALEPH detector at LEP we find M z =91.182±0.026 (exp.) ±0.030 (beam) GeV, Γ z =2.541±0.056 GeV and σ had 0 =41.4±0.8 nb. The partial widths for the hadronic and leptonic channels are Γ had =1804±44 MeV, Γ e + e − =82.1±3.4 MeV, Γ μ + μ − =87.9±6.0 MeV and Γ τ + τ − =86.1±5.6 MeV, in good agreement with the standard model. On the basis of the average leptonic width Γ ℓ + ℓ − =83.9±2.2 MeV, the effective weak mixing angle is found to be sin 2 θ w ( M z )=0.231±0.008. Usin g the partial widths calculated in the standard model, the number of light neutrino families is N ν =3.01±0.15 (exp.)±0.05 (theor.).

4 data tables

Table 1

Penetrating charged particle track selection.

Table 2

Calorimeter selection.

Table 3

Average cross section.

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A Comparison of the Structure Functions F2 of the Proton and the Neutron From Deep Inelastic Muon Scattering at High $Q^2$

The BCDMS collaboration Benvenuti, A.C. ; Bollini, D. ; Bruni, G. ; et al.

Phys.Lett.B 237 (1990) 599-604, 1990.

Inspire Record 285519 DOI 10.17182/hepdata.29734

High statistics data on the structure functions F 2 of the proton and the deutron measured with the same apparatus in deep inelastic muon scattering are used to study the ratio of structure functions of neutron and proton F 2 n / F 2 p and their difference F 2 p - F 2 n . Both measurements are consistent with predictions of the quark-parton model and of QCD.

2 data tables

Table 1

No description provided.

Table 2

No description provided.

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.C 46 (1990) 547-554, 1990.

Inspire Record 284560 DOI 10.17182/hepdata.15279

The cross-sections and the forward-backward charge asymmetries of muon and tau pairs produced ine+e− collisions at$\sqrt s= 35 GeV$ have been measured by the JADE Collaboration. The cross-sections,$\sigma _\mu(\sqrt s= GeV) = 69.79 \pm 1.35 \pm 1.40 pb$ and$\sigma _\mu(\sqrt s= GeV) = 71.72 \pm 1.48 \pm 1.61 pb$, are in agreement with the QED α3 prediction. The charge asymmetries areAμ=−(9.9±1.5±0.5)% andAτ=−(8.1±2.0±0.6)% in agreement with the value −9.2% predicted by the standard model, usingMZ=91.0 GeV and sin2θW=0.230.

2 data tables

Table 1

No description provided.

Table 2

No description provided.

Measurement of the Decay of the $\Z^0$ Into Lepton Pairs

The OPAL collaboration Akrawy, M.Z. ; Alexander, G. ; Allison, J. ; et al.

Phys.Lett.B 235 (1990) 379-388, 1990.

Inspire Record 283146 DOI 10.17182/hepdata.29723

We report on a measurement of the processes e + e − →e + e − , e + e − → μ + μ − , and e + e − → τ + τ − near the Z 0 pole. On the basis of 163 e + e − , 101 μ + μ − and 87 τ + τ − events we obtain Γ ee =89±4±4 MeV, Γ μμ =85±9±6 MeV and Γ ττ =87±10±8 MeV, compatible with the standard model. Combining these with our previous results on hadronic Z 0 decays, we find a hadronic width Γ had =1787±81±90 MeV and an invisible width Γ inv =552±85±71 MeV.

2 data tables

Table 1

Statistical errors only.

Table 2

Statistical errors only.

Measurement of $g$(a) and $g(V$), the Neutral Current Coupling Constants to Leptons

The L3 collaboration Adeva, B. ; Adriani, O. ; Aguilar-Benitez, M. ; et al.

Phys.Lett.B 236 (1990) 109-115, 1990.

Inspire Record 283470 DOI 10.17182/hepdata.29715

We have measured both the rates and the forward-backward asymmetry of ℓ + ℓ − from Z 0 →ℓ + ℓ − (where ℓ= μ , τ ) with the L3 detector. We obtained Γ ℓℓ =88±4±3 MeV and the vector neutral current coupling constant, g v =0.00±0.07 and the axial vector neutral current coupling constant, g A =−0.515±0.015.

2 data tables

Table 1

No description provided.

Table 2

No description provided.

Measurements of the Nucleon Structure Function in the Range 0.002-GeV2 < x < 0.17-GeV2 and 0.2-GeV2 < q2 < 8-GeV**2 in Deuterium, Carbon and Calcium

The European Muon collaboration Arneodo, M. ; Arvidson, A. ; Aubert, J.J. ; et al.

Nucl.Phys.B 333 (1990) 1-47, 1990.

Inspire Record 283347 DOI 10.17182/hepdata.33074

Small angle scattering of 280 GeV positive muons by deuterium, carbon and calcium has been measured at scattering angles down to 2 mrad. The nucleon structure function F 2 extracted from deuterium does not show a significant x dependence in the measured range of Q 2 and its Q 2 dependence is linear in log Q 2 . For calcium, a depletion of F 2 is observed at low x by 30% as compared with the values at x = 0.1 where F 2 (Ca) and F 2 (D) are not significantly different. This depletion is attributed to shadowing. The carbon structure function exhibits a similar, but less pronounced, x dependence. Such behaviour is observed to be independent of Q 2 . The data are consistent with those obtained from other charged lepton experiments both at similar and higher values of x and Q 2 and considerably extend the range of the measurements down to the low values of x to be measured in forthcoming experiments at HERA.

33 data tables

Table 1

Deuterium data. Overall normalization error of 7 pct not included.

Table 2

Deuterium data. Overall normalization error of 7 pct not included.

Table 3

Deuterium data. Overall normalization error of 7 pct not included.

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A MEASUREMENT OF THE Z0 LEPTONIC PARTIAL WIDTHS AND THE FORWARD - BACKWARD ASYMMETRY

A Combined Analysis of the Hadronic and Leptonic Decays of the $\Z^0$

W2 and Q2 dependence of charged hadron and pion multiplicities in neutrino p and anti-neutrino p charged current interactions

A High Statistics Measurement of the Deuteron Structure Functions F2 (X, $Q^2$) and R From Deep Inelastic Muon Scattering at High $Q^2$

A Precise Determination of the Number of Families With Light Neutrinos and of the $Z$ Boson Partial Widths

A Comparison of the Structure Functions F2 of the Proton and the Neutron From Deep Inelastic Muon Scattering at High $Q^2$

Final Results on $\mu$ and Tau Pair Production by the Jade Collaboration at {PETRA}

Measurement of the Decay of the $\Z^0$ Into Lepton Pairs

Measurement of $g$(a) and $g(V$), the Neutral Current Coupling Constants to Leptons

Measurements of the Nucleon Structure Function in the Range 0.002-GeV2 < x < 0.17-GeV2 and 0.2-GeV2 < q2 < 8-GeV**2 in Deuterium, Carbon and Calcium