Eisner, A.M.
E+ E- --> GAMMA X
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rivet Analysis
Photon and light meson production in hadronic Z0 decays.

The OPAL collaboration Ackerstaff, K. ; Alexander, G. ; Allison, John ; et al.
Eur.Phys.J.C 5 (1998) 411-437, 1998.
Inspire Record 470419 DOI 10.17182/hepdata.49498

The inclusive production rates and differential cross-sections of photons and mesons with a final state containing photons have been measured with the OPAL detector at LEP. The light mesons covered by the measurements are the \pi^0, \eta, \rho(770)+-, \omega(782), \eta'(958) and a_0(980)+-. The particle multiplicities per hadronic Z^0 decay, extrapolated to the full energy range, are: = 20.97 +/- 0.02 +/- 1.15, = 9.55 +/- 0.06 +/- 0.75, = 0.97 +/- 0.03 +/- 0.11, = 2.40 +/- 0.06 +/- 0.43, = 1.04 +/- 0.04 +/- 0.14, = 0.14 +/- 0.01 +/- 0.02, = 0.27 +/- 0.04 +/- 0.10. where the first errors are statistical and the second systematic. In general, the results are in agreement with the predictions of the JETSET and HERWIG Monte Carlo models.

15 data tables
Table 1

Particle multiplicities per hadronic decay extrapolated to the full energy range.

Table 2

Photon fragmentation function.

Table 3

Photon fragmentation function.

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rivet Analysis
Studies of quantum chromodynamics with the ALEPH detector

The ALEPH collaboration Barate, R. ; Buskulic, D. ; Decamp, D. ; et al.
Phys.Rept. 294 (1998) 1-165, 1998.
Inspire Record 428072 DOI 10.17182/hepdata.47582

Previously published and as yet unpublished QCD results obtained with the ALEPH detector at LEP1 are presented. The unprecedented statistics allows detailed studies of both perturbative and non-perturbative aspects of strong interactions to be carried out using hadronic Z and tau decays. The studies presented include precise determinations of the strong coupling constant, tests of its flavour independence, tests of the SU(3) gauge structure of QCD, study of coherence effects, and measurements of single-particle inclusive distributions and two-particle correlations for many identified baryons and mesons.

44 data tables
Table 1

Charged particle sphericity distribution.

Table 2

Charged particle aplanarity distribution.

Table 3

Charged particle Thrust distribution.

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rivet Analysis
A Measurement of the Direct Photon Spectrum From the $\Upsilon$ (1s)

The CLEO collaboration Csorna, S.E. ; Mestayer, M.D. ; Panvini, R.S. ; et al.
Phys.Rev.Lett. 56 (1986) 1222, 1986.
Inspire Record 220652 DOI 10.17182/hepdata.20260

We have observed decays of the ϒ(1S) into hadronic final states containing high-energy photons. These are interpreted as coming from the decay ϒ(1S)→γ+gluon+gluon. We compare the shape of the observed photon energy spectrum with several theoretical predictions and deduce the value of the strong-coupling constant αs and the QCD scale parameter ΛMS― (MS― denotes the modified minimal-subtraction scheme) associated with each prediction.

2 data tables
Table 1

DATA TAKEN ON THE PEAK OF THE UPSI(9460).

Table 2

DATA TAKEN ON THE PEAK OF THE UPSI(9460).


Evidence for Direct $\gamma$ Production at Large $x$ in $\psi$ (3100) Decay

Ronan, M.T. ; Trippe, T.G. ; Barbaro-Galtieri, A. ; et al.
Phys.Rev.Lett. 44 (1980) 367, 1980.
Inspire Record 142946 DOI 10.17182/hepdata.20700

The inclusive γ and π0 momentum spectra from ψ(3100) decay have been measured in e+e− annihilation at SPEAR. When the γ spectrum is compared with that expected from π0 decay, an excess of high-momentum γ's is observed. This excess is compared with that predicted by quantum chromodynamics for the decay of the ψ into a γ and two gluons.

4 data tables
Table 1

THE STATISTICAL AND SYSTEMATIC ERRORS ARE GIVEN SEPARATELY AS WELL AS COMBINED IN QUADRATURE FOR THE QUOTED TOTAL ERROR.

Table 2

THE STATISTICAL AND SYSTEMATIC ERRORS ARE GIVEN SEPARATELY AS WELL AS COMBINED IN QUADRATURE FOR THE QUOTED TOTAL ERROR. SYSTEMATIC ERROR IS 17 PCT.

Table 3

QUOTED ERRORS ARE STATISTICAL. SYSTEMATIC ERROR IS 20 PCT. ONLY HALF THE SUM OF THE PI+ AND PI- CROSS SECTIONS IS PLOTTED IN THE FIGURE IN THE JOURNAL.

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