Measurement of Z-pair production in e+ e- collisions and constraints on anomalous neutral gauge couplings

The ALEPH collaboration Schael, S. ; Barate, R. ; Bruneliere, R. ; et al.
JHEP 04 (2009) 124, 2009.
Inspire Record 824816 DOI 10.17182/hepdata.52431

The ZZ production cross section is measured from a data sample corresponding to a total integrated luminosity of 452 pb(-')(1), collected by the ALEPH experiment at LEP at centre-of-mass energies from 192 to 209 GeV. Individual cross sections, ext racted at six centre-of-mass energies, are found to be in agreement with Standard Model calculations. The results are used to set limits on anomalous neutral gauge couplings.

1 data table

Measured E+ E- --> Z0 Z0 cross sections.


Single vector boson production in e+ e- collisions at centre-of-mass energies from 183-GeV to 209-GeV.

The ALEPH collaboration Schael, S. ; Barate, R. ; Bruneliere, R. ; et al.
Phys.Lett.B 605 (2005) 49-62, 2005.
Inspire Record 656811 DOI 10.17182/hepdata.48763

The cross sections for single vector boson production in the We ν and Zee channels are measured from the data collected by the ALEPH detector at LEP for centre-of-mass energies between 183 and 209  GeV. These data correspond to a total integratedluminosity of 683 pb −1 . Single-W production is studied in both hadronic and leptonic decay channels. Hadronic and dimuon decays are used for single-Z production. The measured cross sections agree with the Standard Model predictions.

4 data tables

Measured cross sections for single W production in the leptonic and hadronic decay channels of the W separately and combined.

The measured single Z0 production cross section.

Z0 --> MU+ MU- cross section averaged over all c.m. energies.

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Measurement of W pair production in e+ e- collisions at centre-of-mass energies from 183-GeV to 209-GeV.

The ALEPH collaboration Heister, A. ; Schael, S. ; Barate, R. ; et al.
Eur.Phys.J.C 38 (2004) 147-160, 2004.
Inspire Record 653296 DOI 10.17182/hepdata.48582

The W + W- production cross section is measured from a data sample corresponding to a total integrated luminosity of 683 pb-1, collected by the ALEPH experiment at LEP at centre-of-mass energies from

13 data tables

The measured cross section for the E NU E NU final state. The DSYS error is the typical systematic error.

The measured cross section for the E NU MU NU final state. The DSYS error is the typical systematic error.

The measured cross section for the E NU TAU NU final state. The DSYS error is the typical systematic error.

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Studies of QCD at e+ e- centre-of-mass energies between 91-GeV and 209-GeV.

The ALEPH collaboration Heister, A. ; Schael, S. ; Barate, R. ; et al.
Eur.Phys.J.C 35 (2004) 457-486, 2004.
Inspire Record 636645 DOI 10.17182/hepdata.12794

The hadronic final states observed with the ALEPH detector at LEP in ${\rm e}^ + {\rm e}^-$ annihilation

234 data tables

Mean charged particle multiplicities at different c.m. energies.

XP distribution at c.m. energy 133.0 GeV.

XP distribution at c.m. energy 161.0 GeV.

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Exclusive production of pion and kaon meson pairs in two photon collisions at LEP.

The ALEPH collaboration Heister, A. ; Schael, S. ; Barate, R. ; et al.
Phys.Lett.B 569 (2003) 140-150, 2003.
Inspire Record 626022 DOI 10.17182/hepdata.49730

Exclusive production of π and K meson pairs in two photon collisions is measured with ALEPH data collected between 1992 and 2000. Cross-sections are presented as a function of cos θ ∗ and invariant mass, for | cos θ ∗ |<0.6 and invariant masses between 2.0 and 6.0 GeV/ c 2 (2.25 and 4.0 GeV/ c 2 ) for pions (kaons). The shape of the distributions are found to be well described by QCD predictions but the data have a significantly higher normalization.

4 data tables

Measured angular distribution for pion production.

Measured angular distribution for kaon production.

Measured cross section for pion production as a function of W.

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Study of hadronic final states from double tagged gamma gamma events at LEP.

The ALEPH collaboration Heister, A. ; Schael, S. ; Barate, R. ; et al.
CERN-EP-2003-025, 2003.
Inspire Record 619958 DOI 10.17182/hepdata.49702

The interaction of virtual photons is investigated using double tagged gammagamma events with hadronic final states recorded by the ALEPH experiment at e^+e^- centre-of-mass energies between 188 and 209 GeV. The measured cross section is compared to Monte Carlo models, and to next-to-leading-order QCD and BFKL calculations.

10 data tables

Differential cross section as a function of the relative energy of the scattered electrons.

Differential cross section as a function of the polar angle THETA of the scattered electrons.

Differential cross section as a function of the virtuality Q**2 of the photons.

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Measurement of the hadronic photon structure function F2(gamma)(x, Q**2) in two-photon collisions at LEP

The ALEPH collaboration Heister, A. ; Schael, S. ; Barate, R. ; et al.
Eur.Phys.J.C 30 (2003) 145-158, 2003.
Inspire Record 631231 DOI 10.17182/hepdata.43218

The hadronic photon structure function $F_2^\gamma(x,Q^2)$ is measured from data taken with the ALEPH detector at LEP. At centre-of-mass energies between

4 data tables

Measured value of F2/ALPHAE at a mean Q**2 of 17.3 GeV**2.

Measured value of F2/ALPHAE at a mean Q**2 of 67.2 GeV**2.

Statistical correlation coefficients for the F2 measurements at Q**2 = 17.3 GeV**2.

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Measurement of the inclusive D*+- production in gamma gamma collisions at LEP.

The ALEPH collaboration Heister, A. ; Schael, S. ; Barate, R. ; et al.
Eur.Phys.J.C 28 (2003) 437-449, 2003.
Inspire Record 612223 DOI 10.17182/hepdata.48891

The inclusive production of D$^{*\pm}$ mesons in two-photon collisions is measured with the ALEPH detector at $\epem$ centre-of-mass energies from 183$\unit{GeV}$ to 209$\unit{GeV}$. A total of $360 \pm 27$ D$^{*\pm}$ meson events were observed from an integrated luminosity of 699\unit{pb^{-1}}$. Contributions from direct and single-resolved rocesses are separated using the ratio of the transverse momentum $p_{\rm t}^{\rm D^{*\pm}}$ of the D$^{*\pm}$ to the visible invariant mass $W_{\mathrm{vis}}$ of the event. Differential cross sections of D$^{*\pm}$ production as functions of $p_{\rm t}^{\rm D^{*\pm}}$ and the pseudorapidity $|\eta^{\rm D^{*\pm}}| $ are measured in the range $ 2\unit{GeV}/c < p_{\rm t}^{\rm D^{*\pm}} < 12\unit{GeV}/c $ and $ |\eta^{\rm D^{*\pm}}| < 1.5 $. They are compared to next-to-leading order (NLO)perturbative QCD calculations. The extrapolation of the integrated visible D$^{*\pm}$ cross section to the total charm cross section, based on the Pythia Monte Carlo program, yields $ \sigma (\epem \to \epem \ccbar)_ {=197\unit{GeV}} = 731 \pm 74_{\mathrm{stat}} \pm 47_{\mathrm{syst}} \pm 157_{\mathrm{extr}} \unit{pb} $.

7 data tables

Total extrapolated charm production cross section. The second DSYS error isdue to the uncertainty in the extrapolation.

Visible cross section with the acceptance range.

Visible cross section within the acceptance ranges for the three decay modes observed.

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Inclusive production of the omega and eta mesons in Z decays, and the muonic branching ratio of the omega.

The ALEPH collaboration Heister, A. ; Schael, S. ; Barate, R. ; et al.
Phys.Lett.B 528 (2002) 19-33, 2002.
Inspire Record 569165 DOI 10.17182/hepdata.48894

The inclusive production of the omega(782) vector meson in hadronic Z decays is measured and compared to model predictions. The analysis is based on 4 million hadronic Z decays recorded by the ALEPH detector between 1991 and 1995. The production rate for x_p = p_meson/p_beam > 0.05 is measured in the omega -> pi^+ pi^- pi^0 decay mode and found to be 0.585 +- 0.019_stat +- 0.033_sys per event. Inclusive eta meson production is also measured in the same decay channel for x_p > 0.10, obtaining 0.355 +- 0.011_stat +- 0.024_sys per event. The branching ratio for omega -> mu^+ mu^- is investigated. A total of 18.1 +- 5.9 events are observed, from which the muonic branching ratio is measured for the first time to be BR(omega -> mu^+ mu^-) = (9.0 +- 2.9_stat +- 1.1_sys)*10^-5.

3 data tables

Extrapolation using JETSET 7.4 is used to correct down to X = 0.0. The second DSYS error, where relevant, shows the estimated uncertainty on the extrapolation.

Production rate and differential cross sections for the ETA.

Production rate and differential cross sections for the OMEGA.


Measurement of the tau polarisation at LEP.

The ALEPH collaboration Heister, A. ; Schael, S. ; Barate, R. ; et al.
Eur.Phys.J.C 20 (2001) 401-430, 2001.
Inspire Record 555653 DOI 10.17182/hepdata.49751

The polarisation of $\tau$'s produced in Z decay is measured using 160 pb$^{-1}$ of data accumulated at LEP by the ALEPH detector between 1990 and 1995. The variation of the polarisation with polar angle yields the two parameters ${\cal A}_e = 0.1504 \pm 0.0068 $ and ${\cal A}_{\tau} = 0.1451 \pm 0.0059$ which are consistent with the hypothesis of $e$-$\tau$ universality. Assuming universality, the value ${\cal A}_{e{-}\tau} = 0.1474 \pm 0.0045$ is obtained from which the effective weak mixing angle $\sin^2 {\theta_{\mathrm{W}}^{\mathrm{eff}}} =0.23147 \pm 0.00057 $ is derived.

1 data table

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