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E+ E- --> QUARK QUARKBAR
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Measurement of the cross section of W-boson pair production at LEP.

The L3 collaboration Achard, P. ; Adriani, O. ; Aguilar-Benitez, M. ; et al.
Phys.Lett.B 600 (2004) 22-40, 2004.
Inspire Record 658254 DOI 10.17182/hepdata.48792

The cross section of W-boson pair-production is measured with the L3 detector at LEP. In a data sample corresponding to a total luminosity of 629.4/pb, collected at centre-of-mass energies ranging from 189 to 209 GeV, 9834 four-fermion events with W bosons decaying into hadrons or leptons are selected. The total cross section is measured with a precision of 1.4 % and agrees with the Standard Model expectation. Assuming charged-lepton universality, the branching fraction for hadronic W-boson decays is measured to be: Br(W-->hadrons) = 67.50 +- 0.42 (stat.) +- 0.30(syst.) %, in agreement with the Standard Model. Differential cross sections as a function of the W- production angle are also measured for the semi-leptonic channels qqev and qqmv.

11 data tables
Table 1

Measured cross section for the process E+ E- --> LEPTON NU LEPTON NU.

Table 2

Measured cross section for the process E+ E- --> QUARK QUARKBAR ELECTRON NEUTRINO.

Table 3

Measured cross section for the process E+ E- --> QUARK QUARKBAR MUON NEUTRINO.

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A Measurement of the Z0 ---> b anti-b forward - backward asymmetry

The L3 collaboration Adeva, B. ; Adriani, O. ; Aguilar-Benitez, M. ; et al.
Phys.Lett.B 252 (1990) 713-721, 1990.
Inspire Record 301901 DOI 10.17182/hepdata.29506

We have measured the forward-backward asymmetry in Z 0 → b b decays using hadronic events containing muons and electrons. The data sample corresponds to 118 200 hadronic events at √ s ≈ M z . From a fit to the single and dilepton p and P ⊥ spectra, we determine A b b =0.130 −0.042 +0.044 including the correction for B 0 − B 0 mixing.

3 data tables
Table 1

Observed asymmetry from fit to single and dilepton P and PT spectra assuming no mixing.

Table 2

Asymmetry corrected for the effects of mixing using the L3 observed mixing parameter chi(B) = 0.178 +0.049,-0.040.

Table 3

SIN2TW determined from the asymmetry measurement.


Measurement of $\Z^0 \to b \bar{b}$ Decay Properties

The L3 collaboration Adeva, B. ; Adriani, O. ; Aguilar-Benitez, M. ; et al.
Phys.Lett.B 241 (1990) 416-424, 1990.
Inspire Record 295040 DOI 10.17182/hepdata.29716

We have measured the properties of Z 0 → b b decays using a sample of 944 inclusive muon events, corresponding to 18 000 hadron events obtained with the L3 detector at LEP. We measured the partial decay width of the Z 0 into b b , Γ b b =353±48 MeV , and we determined the vector coupling of the Z 0 to the b quark; g rmv 2 (b)=0.095±0.047. We measured the forward-backward charge asymmetry in e + e − → b b events at √ s ≈ M v , and obtained A b b =13.3±9.9% .

1 data table
Table 1

BOTTOM quark charge asymmetry measurement.