E+ E- Scattering
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Study of hadronic events and measurements of alpha(s) between 30-GeV and 91-GeV.

The L3 collaboration Acciarri, M. ; Adriani, O. ; Aguilar-Benitez, M. ; et al.
Phys.Lett.B 411 (1997) 339-353, 1997.
Inspire Record 445998 DOI 10.17182/hepdata.47465

We have studied the structure of hadronic events with a hard, isolated photon in the final state (e + e − → Z → hadrons + γ) in the 3.6 million hadronic events collected with the L3 detector at centre-of-mass energies around 91 GeV. The centre-of-mass energy of the hadronic system is in the range 30 GeV to 86 GeV. Event shape variables have been measured at these reduced centre-of-mass energies and have been compared with the predictions of different QCD Monte Carlo programs. The event shape variables and the energy dependence of their mean values are well reproduced by QCD models. We fit distributions of several global event shape variables to resummed O (α s 2 ) calculations to determine the strong coupling constant α s over a wide range of energies. We find that the strong coupling constant α s decreases with increasing energy, as expected from QCD.

6 data tables
Table 1

No description provided.

Table 2

No description provided.

Table 3

No description provided.

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Measurement of muon pair production at 50-GeV < s**(1/2) < 86-GeV at LEP

The L3 collaboration Acciarri, M. ; Adam, A. ; Adriani, O. ; et al.
Phys.Lett.B 374 (1996) 331-340, 1996.
Inspire Record 416744 DOI 10.17182/hepdata.47586

Using the data recorded with the L3 detector at LEP, we study the process e + e − → μ + μ − ( γ ) for events with hard initial-state photon radiation. The effective centre-of-mass energies of the muons range from 50 GeV to 86 GeV. The data sample corresponds to an integrated luminosity of 103.5 pb −1 and yields 293 muon-pair events with a hard photon along the beam direction. The events are used to determine the cross sections and the forward-backward charge asymmetries at centre-of-mass energies below the Z resonance.

3 data tables
Table 1

Here S refers to the reduced centre-of-mass energy.

Table 2

Forward-Backward Asymmetry from fit as function of the reduced centre-of-mass energy.

Table 3

Background corrected Forward-Backward Asymmetry as function of the reduced centre-of-mass energy.


Neutral kaon and lambda production in electron - positron annihilation at 29-GeV and the Z boson resonance

Fordham, C. ;
SLAC-0374, 1990.
Inspire Record 300503 DOI 10.17182/hepdata.18797

None

26 data tables
Table 1

No description provided.

Table 2

No description provided.

Table 3

No description provided.

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Determination of $\alpha^- s$ From a Differential Jet Multiplicity Distribution at {SLC} and {PEP}

Komamiya, Sachio ; Le Diberder, F. ; Abrams, G.S. ; et al.
Phys.Rev.Lett. 64 (1990) 987, 1990.
Inspire Record 283630 DOI 10.17182/hepdata.19937

We measured the differential jet-multiplicity distribution in e+e− annihilation with the Mark II detector. This distribution is compared with the second-order QCD prediction and αs is determined to be 0.123±0.009±0.005 at √s≊MZ (at the SLAC Linear Collider) and 0.149±0.002±0.007 at √s=29 GeV (at the SLAC storage ring PEP). The running of αs between these two center-of-mass energies is consistent with the QCD prediction.

2 data tables
Table 1

DIFFERENTIAL JET MULTIPLICITIES.

Table 2

DIFFERENTIAL JET MULTIPLICITIES.