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QCD results from studies of hadronic events produced in e+ e- annihilations at S**(1/2) = 183-GeV

The L3 collaboration Acciarri, M. ; Adriani, O. ; Aguilar-Benitez, M. ; et al.
Phys.Lett. B444 (1998) 569-582, 1998.
Inspire Record 477808 DOI 10.17182/hepdata.49364
1 data table

These data are superceded by the analysis presented in Acciarri et al PL B489,65.


QCD studies in $e^{+} e^{-}$ annihilation from 30-GeV to 189-GeV

The L3 collaboration Acciarri, M. ; Achard, P. ; Adriani, O. ; et al.
Phys.Lett. B489 (2000) 65-80, 2000.
Inspire Record 527988 DOI 10.17182/hepdata.21126

We present results obtained from a study of the structure of hadronic events recorded by the L3 detector at various centre-of-mass energies. The distributions of event shape variables and the energy dependence of their mean values are measured from 30GeV to 189GeV and compared with various QCD models. The energy dependence of the moments of event shape variables is used to test a power law ansatz for the non-perturbative component. We obtain a universal value of the non-perturbative parameter alpha_0 = 0.537 +/- 0.073. From a comparison with resummed O(alpha_s^2) QCD calculations, we determine the strong coupling constant at each of the selected energies. The measurements demonstrate the running of alpha_s as expected in QCD with a value of alpha_s(m_Z) = 0.1215 +/- 0.0012 (exp) +/- 0.0061 (th).

22 data tables

Distribution for THRUST at c.m. energy 189 GeV.

Distribution for Heavy Jet Mass at c.m. energy 189 GeV.

Distribution for Total Jet Broadening at c.m. energy 189 GeV.

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Inclusive production of pi0, eta, eta-prime (958), K0(S) and lambda in two jet and three jet events from hadronic Z decays

The ALEPH collaboration Barate, R. ; Decamp, D. ; Ghez, Philippe ; et al.
Eur.Phys.J. C16 (2000) 613, 2000.
Inspire Record 507531 DOI 10.17182/hepdata.49106
25 data tables

Inclusive cross section for PI0 production in hadronic events.

Inclusive cross section for ETA production in hadronic events.

Inclusive cross section for ETAPRIME production in hadronic events.

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Measurement of the jet width in $\gamma \gamma$ collisions and in $e^{+} e^{-}$ annihilation process at TRISTAN

The TOPAZ collaboration Adachi, K. ; Hayashii, H. ; Miyabayashi, K. ; et al.
Phys.Lett. B451 (1999) 256-266, 1999.
Inspire Record 494502 DOI 10.17182/hepdata.43768

The shape of jets produced in (quasi-) real photon-photon collisions as well as in e^+e^- annihilation process has been studied with a cone jet finding algorithm, using the data taken with the TOPAZ detector at the TRISTAN e^+e^- collider at an average center-of-mass energy of 58 GeV. The results are presented in terms of the jet width as a function of the jet transverse energy(E^{jet}_T) as well as a scaled transverse jet energy, x_T(=2E^{jet}_T/root(s)). The jet width narrows as E^{jet}_T increases; however, at the same value of E^{jet}_T the jet width in gamma-gamma collisions at TRISTAN is significantly narrower than that in gamma p collisions at HERA. By comparing our results with the data in other reactions, it has been shown that the jet width in gamma-gamma, gamma p, p\bar{p} collisions as well as the e^+e^- annihilation process has an approximate scaling behavior as a function of x_T.

2 data tables

The jet width is defined as the full width at the half maximum of the distribution of the transverse energy flow.

The jet width is defined as the full width at the half maximum of the distribution of the transverse energy flow.


A Study of parton fragmentation in hadronic Z0 decays using Lambda anti-Lambda correlations

The OPAL collaboration Abbiendi, G. ; Ackerstaff, K. ; Alexander, G. ; et al.
Eur.Phys.J. C13 (2000) 185-195, 2000.
Inspire Record 474010 DOI 10.17182/hepdata.49312

The correlated production of Lambda and Lambdabar baryons has been studied using 4.3 million multihadronic Zo decays recorded with the OPAL detector at LEP. Di-lambda pairs were investigated in the full data sample and for the first time also in 2-jet and 3-jet events selected with the k_t algorithm. The distributions of rapidity differences from correlated Lambda-Lambdabar pairs exhibit short-range, local correlations and prove to be a sensitive tool to test models, particularly for 2-jet events. The JETSET model describes the data best but some extra parameter tuning is needed to improve agreement with the experimental results in the rates and the rapidity spectra simultaneously. The recently developed modification of JETSET, the MOdified Popcorn Scenarium (MOPS), and also HERWIG do not give satisfactory results. This study of di-lambda production in 2- and 3-jet events supports the short-range compensation of quantum numbers.

5 data tables

Average multipicity of LAMBDA pairs in hadronic events.

Average multipicity of LAMBDA pairs in 2-Jet events.

Average multipicity of LAMBDA pairs in 3-Jet events.

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Study of the structure of hadronic events and determination of alpha-s at s**(1/2) = 130-GeV and 136-GeV

The L3 collaboration Acciarri, M. ; Adam, A. ; Adriani, O. ; et al.
Phys.Lett. B371 (1996) 137-148, 1996.
Inspire Record 404916 DOI 10.17182/hepdata.48010
3 data tables

Mean values of the event shape variables.

Mean charged particle multiplicity.

The value of alpha_s from the fits to the event shape variables : thrust (THRUST), scale heavy jet mass (MH**2/S), total jet broadening (BT)and wide jet broadening (BW). The last value is combined result (COMBINED). The second systematic error is due to uncertainties in the theory.


A Determination of alpha-s in e+ e- annihilation at s**(1/2) = 57.3-GeV

The AMY collaboration Li, Y.K. ; Sagawa, H. ; Bodek, A. ; et al.
Phys.Lett. B355 (1995) 394-400, 1995.
Inspire Record 406129 DOI 10.17182/hepdata.6546
6 data tables

The data are compared to the predictions of Monte-Carlo.

Using the p-scheme for jet clustering.

Using the E-scheme for jet clustering.

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A Study of mean subjet multiplicities in two and three jet hadronic Z0 decays

The OPAL collaboration Akers, R. ; Alexander, G. ; Allison, John ; et al.
Z.Phys. C63 (1994) 363-376, 1994.
Inspire Record 372997 DOI 10.17182/hepdata.48236
4 data tables

Ratio of multiplicities of sub-jets from 3 and 2 jet samples. Data are corrected to the hadron level and have combined statistical and systematic errors.

Sub-jet multiplicity for 3 jet sample. Data corrected to the hadron level and have combined statistical and systematic errors.

Sub-jet multiplicity for 2 jet sample. Data corrected to the hadron level and have combined statistical and systematic errors.

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QCD studies using a cone based jet finding algorithm for $e^{+} e^{-}$ collisions at LEP

The OPAL collaboration Akers, R. ; Alexander, G. ; Allison, John ; et al.
Z.Phys. C63 (1994) 197-212, 1994.
Inspire Record 373000 DOI 10.17182/hepdata.48238
16 data tables

Measured 2 jet production rate as a function of EPSILON, the minimum energy of a jet for a fixed cone radius R = 0.7 radians.

Measured 2 jet production rate as a function of R, the jet cone radius, for a fixed value of the minimum jet energy, EPSILON, of 7 GeV.

Measured 3 jet production rate as a function of EPSILON, the minimum energy of a jet for a fixed cone radius R = 0.7 radians.

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Charged particle multiplicity distributions for fixed number of jets in Z0 hadronic decays

The DELPHI collaboration Abreu, P. ; Adam, W. ; Adami, F. ; et al.
Z.Phys. C56 (1992) 63-76, 1992.
Inspire Record 334948 DOI 10.17182/hepdata.14533
3 data tables

Corrected charged particle multiplicity for jet resolution parameter YCUT = 0.01.

Corrected charged particle multiplicity for jet resolution parameter YCUT = 0.02.

Corrected charged particle multiplicity for jet resolution parameter YCUT = 0.04.


A Study of the recombination scheme dependence of jet production rates and of alpha-s (m(Z0)) in hadronic Z0 decays

The OPAL collaboration Akrawy, M.Z. ; Alexander, G. ; Allison, John ; et al.
Z.Phys. C49 (1991) 375-384, 1991.
Inspire Record 299833 DOI 10.17182/hepdata.15085
9 data tables

Jet production rates using the E0 recombination scheme.

Jet production rates using the E recombination scheme.

Jet production rates using the p0 recombination scheme.

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A Study of jet rates and measurement of alpha-s at the Z0 resonance

Lauber, Jan A. ;
PhD Thesis, 1993.
Inspire Record 353248 DOI 10.17182/hepdata.18664
9 data tables

Jet production rates using the JADE recombination scheme.

Jet production rates using the DURHAM recombination scheme.

Jet production rates using the E recombination scheme.

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A Global determination of $\alpha^- s$ (M(z0) ) at LEP

The OPAL collaboration Acton, P.D. ; Alexander, G. ; Allison, John ; et al.
Z.Phys. C55 (1992) 1-24, 1992.
Inspire Record 333079 DOI 10.17182/hepdata.14606
16 data tables

Differential jet mass distribution for the heavier jet using method T. The data are corrected for the finite acceptance and resolution of the detector and for initial state photon radiation.

Differential jet mass distribution for the jet mass difference using methodT. The data are corrected for the finite acceptance and resolution of the detec tor and for initial state photon radiation.

Differential jet mass distribution for the heavier jet using method M. The data are corrected for the finite acceptance and resolution of the detector and for initial state photon radiation.

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Determination of alpha(s) in second order QCD from hadronic Z decays

The DELPHI collaboration Abreu, P. ; Adam, W. ; Adami, F. ; et al.
Z.Phys. C54 (1992) 55-74, 1992.
Inspire Record 333272 DOI 10.17182/hepdata.14603
9 data tables

Experimental differential Thrust distributions.

Experimental differential Oblateness distributions.

Experimental differential C-parameter distributions.

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Determination of alpha-s from jet multiplicities measured on the Z0 resonance

The L3 collaboration Adeva, B. ; Adriani, O. ; Aguilar-Benitez, M. ; et al.
Phys.Lett. B248 (1990) 464-472, 1990.
Inspire Record 298078 DOI 10.17182/hepdata.29651
2 data tables

Errors are combined statistical and systematic uncertainties.

No description provided.


Experimental Investigation of the Energy Dependence of the Strong Coupling Strength

The JADE collaboration Bethke, S. ; Allison, John ; Ambrus, K. ; et al.
Phys.Lett. B213 (1988) 235-241, 1988.
Inspire Record 263579 DOI 10.17182/hepdata.29894
4 data tables

No description provided.

No description provided.

No description provided.

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Charged Particle Multiplicity Distributions in $e^+ e^-$ Annihilation at 29-{GeV}: A Comparison With Hadronic Data

Derrick, M. ; Gan, K.K. ; Kooijman, P. ; et al.
Z.Phys. C35 (1987) 323, 1987.
Inspire Record 235873 DOI 10.17182/hepdata.15773
4 data tables

Charged Particle Multiplicity distributions for single jet and whole event from the two jet sample. The numerical values are given in the paper Derrick et al, PR D34 (86) 3304, and are coded in this database as (<a href=http://durpdg.dur.ac.uk/scripts/reacsearch.csh/TESTREAC/red+1437> RED = 1437 </a>).

Single Jet Mean Multiplicities.

Total event charged multiplicities.

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Comparison of the Particle Flow in $q \bar{q} \gamma$ and $q \bar{q} g$ Events From $e^+ e^-$ Annihilations at {PETRA}

The JADE collaboration Ould Saada, F. ; Allison, John ; Ambrus, K. ; et al.
Z.Phys. C39 (1988) 1, 1988.
Inspire Record 260834 DOI 10.17182/hepdata.15623
1 data table

Data requested from authors.