Studies of hadronic event structure in e+ e- annihilation from 30-GeV to 209-GeV with the L3 detector

The L3 collaboration Achard, P. ; Adriani, O. ; Aguilar-Benitez, M. ; et al.
Phys.Rept. 399 (2004) 71-174, 2004.
Inspire Record 652683 DOI 10.17182/hepdata.54900

In this Report, QCD results obtained from a study of hadronic event structure in high energy e^+e^- interactions with the L3 detector are presented. The operation of the LEP collider at many different collision energies from 91 GeV to 209 GeV offers a unique opportunity to test QCD by measuring the energy dependence of different observables. The main results concern the measurement of the strong coupling constant, \alpha_s, from hadronic event shapes and the study of effects of soft gluon coherence through charged particle multiplicity and momentum distributions.

68 data tables

Jet fractions using the JADE algorithm as a function of the jet resolution parameter YCUT at c.m. energy 130.1 GeV.

Jet fractions using the JADE algorithm as a function of the jet resolution parameter YCUT at c.m. energy 136.1 GeV.

Jet fractions using the JADE algorithm as a function of the jet resolution parameter YCUT at c.m. energy 161.3 GeV.

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Charged and Identified Particles in the Hadronic Decay of W Bosons and in e+e- -> q qbar from 130 to 200 GeV

The DELPHI collaboration Abreu, P. ; Adam, W. ; Adye, T. ; et al.
Eur.Phys.J.C 18 (2000) 203-228, 2000.
Inspire Record 526164 DOI 10.17182/hepdata.43294

Inclusive distributions of charged particles in hadronic W decays are experimentally investigated using the statistics collected by the DELPHI experiment at LEP during 1997, 1998 and 1999, at centre-of-mass energies from 183 to around 200 GeV. The possible effects of interconnection between the hadronic decays of two Ws are not observed. Measurements of the average multiplicity for charged and identified particles in q qbar and WW events at centre-of-mass energies from 130 to 200 GeV and in W decays are presented. The results on the average multiplicity of identified particles and on the position xi^* of the maximum of the xi_p = -log(2p/sqrt(s)) distribution are compared with predictions of JETSET and MLLA calculations.

16 data tables

Corrected multiplicites and dispersions of charged particles produced in hadronic decays from QQBAR events. The 200 GeV results are a weighted average fromthe 192, 196 and 200 GeV data.

Average multiplicities of identified hadrons produced in hadronic decays from QQBAR events.

Corrected multiplicites and dispersions of charged particles produced in fully hadronic W decays from two W 4Q and 2Q events.

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Studies of QCD in e+ e- --> hadrons at E(cm) = 130-GeV and 136-GeV.

The ALEPH collaboration Buskulic, D. ; De Bonis, I. ; Decamp, D. ; et al.
Z.Phys.C 73 (1997) 409-420, 1997.
Inspire Record 421546 DOI 10.17182/hepdata.47802

None

8 data tables

Inclusive charged particle distribution as a function of XP.

Inclusive charged particle distribution as a function of rapidity (YRAP).

Inclusive charged particle distribution as a function of PT in the event plane.

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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.B 371 (1996) 137-148, 1996.
Inspire Record 404916 DOI 10.17182/hepdata.48010

We present a study of the structure of hadronic events recorded by the L3 detector at center-of-mass energies of 130 and 136 GeV. The data sample corresponds to an integrated luminosity of 5 pb −1 collected during the high energy run of 1995. The shapes of the event shape distributions and the energy dependence of their mean values are well reproduced by QCD models. From a comparison of the data with resummed O (α s 2 ) QCD calculations, we determine the strong coupling constant to be α s (133 GeV) = 0.107 ± 0.005(exp) ± 0.006(theor).

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.