A study of the energy evolution of event shape distributions and their means with the DELPHI detector at LEP.

The DELPHI collaboration Abdallah, J. ; Abreu, P. ; Adam, W. ; et al.
Eur.Phys.J.C 29 (2003) 285-312, 2003.
Inspire Record 620250 DOI 10.17182/hepdata.13029

Infrared and collinear safe event shape distributions and their mean values are determined in e+e- collisions at centre-of-mass energies between 45 and 202 GeV. A phenomenological analysis based on power correction models including hadron mass effects for both differential distributions and mean values is presented. Using power corrections, alpha_s is extracted from the mean values and shapes. In an alternative approach, renormalisation group invariance (RGI) is used as an explicit constraint, leading to a consistent description of mean values without the need for sizeable power corrections. The QCD beta-function is precisely measured using this approach. From the DELPHI data on Thrust, including data from low energy experiments, one finds beta_0 = 7.86 +/- 0.32 for the one loop coefficient of the beta-function or, assuming QCD, n_f = 4.75 +/- 0.44 for the number of active flavours. These values agree well with the QCD expectation of beta_0=7.67 and n_f=5. A direct measurement of the full logarithmic energy slope excludes light gluinos with a mass below 5 GeV.

71 data tables

1-THRUST distribution.

THRUST-MAJOR distribution.

THRUST-MINOR distribution.

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Measurement of three jet distributions sensitive to the gluon spin in e+ e- annihilations at S**(1/2) = 91-GeV

The OPAL collaboration Alexander, G. ; Allison, John ; Allport, P.P. ; et al.
Z.Phys.C 52 (1991) 543-550, 1991.
Inspire Record 317142 DOI 10.17182/hepdata.14852

None

4 data tables

Data at Parton level.

Ratio data/(Monte Carlo) at Parton level.

Data at Parton level.. Distribution of Ellis-Karliner angle.

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Study of Hadronic Decays of the $\Z^0$ Boson

The DELPHI collaboration Aarnio, P. ; Abreu, P. ; Adam, W. ; et al.
Phys.Lett.B 240 (1990) 271-282, 1990.
Inspire Record 294894 DOI 10.17182/hepdata.49562

Hadronic decays of Z 0 bosons are studied in the Delphi detector. Global event variables and singel particles inclusive distributions are compared with QCD-based predictions. The mean charged multiplicity is found to be 20.6±1.0 (stat+syst). The mean values of the sphericity, aplanarity, thrust, minor value, p in T and p out T are compared with values found at lower energy e + e − colliders.

13 data tables

Corrected Sphericity distribution. Statistical errors only.

Corrected Aplanarity distribution. Statistical errors only.

Corrected Q3-Q2 distribution. Statistical errors only.

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