An Improved measurement of alpha-s (M (Z0)) using energy correlations with the OPAL detector at LEP

The OPAL collaboration Acton, P.D. ; Alexander, G. ; Allison, J. ; et al.
Phys.Lett.B 276 (1992) 547-564, 1992.
Inspire Record 321657 DOI 10.17182/hepdata.29245

We report on an improved measurement of the value of the strong coupling constant σ s at the Z 0 peak, using the asymmetry of the energy-energy correlation function. The analysis, based on second-order perturbation theory and a data sample of about 145000 multihadronic Z 0 decays, yields α s ( M z 0 = 0.118±0.001(stat.)±0.003(exp.syst.) −0.004 +0.0009 (theor. syst.), where the theoretical systematic error accounts for uncertainties due to hadronization, the choice of the renormalization scale and unknown higher-order terms. We adjust the parameters of a second-order matrix element Monte Carlo followed by string hadronization to best describe the energy correlation and other hadronic Z 0 decay data. The α s result obtained from this second-order Monte Carlo is found to be unreliable if values of the renormalization scale smaller than about 0.15 E cm are used in the generator.

2 data tables

Value of LAMBDA(MSBAR) and ALPHA_S.. The first systematic error is experimental, the second is from theory.

The EEC and its asymmetry at the hadron level, unfolded for initial-state radiation and for detector acceptance and resolution. Errors include full statistical and systematic uncertainties.


Intermittency in hadronic decays of the Z0

The OPAL collaboration Akrawy, M.Z. ; Alexander, G. ; Allison, J. ; et al.
Phys.Lett.B 262 (1991) 351-361, 1991.
Inspire Record 314631 DOI 10.17182/hepdata.29397

A factorial moment analysis has been performed on the differential multiplicity distributions of hadronic final states of the Z 0 recorded with the OPAL detector at LEP. The moments of the one-dimensional rapidity and the two-dimensional rapidity versus azimuthal angle distributions are found to exhibit “intermittent” behaviour attributable to the jet structure of the events. The moments are reproduced by both parton shower and matrix element QCD based hadronisation models. No evidence for fluctuations beyond those attributable to jet structure is observed.

3 data tables

Corrected factorial moments of the rapidity distribution with respect to the sphericity axis. The errors shown are statistical only but include the statistical error onthe correction factor, added in quadrature.

Corrected factorial moments of the rapidity distribution with respect to the electron beam axis. The errors shown are statistical only but include the statistical error onthe correction factor, added in quadrature.

Corrected factorial moments of the rapidity (with respect to the sphericityaxis) versus PHI distribution. For each point the NUMBER of bins are constructe d from equal numbers of YRAP and PHI bins. The errors shown are statistical only but include the statistical error onthe correction factor, added in quadrature.


Decay of the psi(3770) to Light Hadrons

The CLEO collaboration Adams, G.S. ; Anderson, M. ; Cummings, J.P. ; et al.
Phys.Rev.D 73 (2006) 012002, 2006.
Inspire Record 691720 DOI 10.17182/hepdata.52474

We describe a search for psi(3770) decay to two-body non-DDbar final states in e+e- data produced by the CESR collider and analyzed with the CLEO-c detector. Vector-pseudoscalar production of Rho0Pi0, Rho+Pi-, OmegaPi0, PhiPi0, RhoEta, OmegaEta, PhiEta, RhoEtaPrime, OmegaEtaPrime, PhiEtaPrime, Kstar0 K0bar, and Kstar+K- is studied along with that of BOnePi (BOne0Pi0 and BOne+Pi-) and Pi+Pi-Pi0. A statistically significant signal is found for PhiEta, at an excess cross section of (2.4 +- 0.6) pb [Gamma_{PhiEta} (psi(3770)) =(74 +- 16)Mev], and a suggestive suppression of Pi+Pi-Pi0 and RhoPi. We conclude with form factor determinations for OmegaPi0, RhoEta, and RhoEtaPrime.

1 data table

Cross sections at 3.671 and 3.773 GeV.


Total Cross-Section for Hadron Production by electron-Positron Annihilation Between 2.4-GeV and 5.0-GeV Center-Of-Mass Energy

Augustin, J.E. ; Boyarski, A. ; Breidenbach, Martin ; et al.
Phys.Rev.Lett. 34 (1975) 764, 1975.
Inspire Record 100592 DOI 10.17182/hepdata.21227

The total cross section for hadron production by e+e− annihilation has been measured at center-of-mass energies between 2.4 and 5.0 GeV. Aside from the very narrow resonances ψ(3105) and ψ(3695), the cross section varies between 32 and 17 nb over this region with structure in the vicinity of 4.1 GeV.

2 data tables

No description provided.

MEAN CHARGED MULTIPLICITY. ERRORS ARE STATISTICAL ONLY.


Discovery of a Narrow Resonance in $e^+ e^-$ Annihilation

The SLAC-SP-017 collaboration Augustin, J.E. ; Boyarski, A. ; Breidenbach, Martin ; et al.
Phys.Rev.Lett. 33 (1974) 1406-1408, 1974.
Inspire Record 91761 DOI 10.17182/hepdata.21247

We have observed a very sharp peak in the cross section for e+e−→hadrons, e+e−, and possibly μ+μ− at a center-of-mass energy of 3.105±0.003 GeV. The upper limit to the full width at half-maximum is 1.3 MeV.

1 data table

No description provided.


The Discovery of a Second Narrow Resonance in e+ e- Annihilation

Abrams, G.S. ; Briggs, D. ; Chinowsky, William ; et al.
Phys.Rev.Lett. 33 (1974) 1453-1455, 1976.
Inspire Record 91611 DOI 10.17182/hepdata.21287

We have observed a second sharp peak in the cross section for e+e−→hadrons at a center-of-mass energy of 3.695±0.004 GeV. The upper limit of the full width at half-maximum is 2.7 MeV.

1 data table

No description provided.


Inclusive Production of $D$ Mesons in $e^+ e^-$ Annihilation at 7-{GeV}

Rapidis, P.A. ; Feldman, G.J. ; Abrams, G.S. ; et al.
Phys.Lett.B 84 (1979) 507-510, 1979.
Inspire Record 133123 DOI 10.17182/hepdata.27331

Inclusive momentum and energy spectra of neutral and charged D-mesons produced in e + e − annihilation at energies near 7 GeV are presented. The slope of the energy spectrum is similar to the charged pion spectrum at the same energy. The inclusive cross section σ(e + e − → D or D + anything) at 7 GeV is 4.8±1.3 nb.

4 data tables

No description provided.

No description provided.

SCALING VARIABLE IS X(P=3,DEF=2*E(P=3)/SQRT(S)) > 0.54.

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$\pi^+$ $\pi^-$ production in $e^+$ $e^-$ collisions and $\rho$-$\omega$ interference

Augustin, J.E. ; Benaksas, D. ; Buon, J. ; et al.
(1969) 35, 1969.
Inspire Record 58289 DOI 10.17182/hepdata.37427

None

1 data table

RELATIVE PRODUCTION OF PION PAIRS WITHOUT RADIATIVE CORRECTIONS.


Study of electron-positron annihilation into pi-plus pi-minus on the rho-neutral resonance

Augustin, J.E. ; Bizot, J.C. ; Buon, J. ; et al.
Phys.Lett.B 28 (1969) 508-512, 1969.
Inspire Record 56683 DOI 10.17182/hepdata.29076

The electromagnetic form factor of the pion has been determined in the ϱ o resonance region by measuring the absolute cross section of the reaction e + e − → π + π − with the Orsay storage ring. More than 800 pion pairs have been detected. The excitation curve has been fitted with a Breit-Wigner formula which leads to the following values: σ peak = (1.69 ± 0.21) 10 −30 cm 2 ; m ϱ = (770 ± 4) MeV ; Γ ϱ = (111 ± 6) MeV . The partial width of the ϱ o going into e + e − thus obtained is: Γ ϱ → e + e − =(7.36±0.7) keV .

1 data table

No description provided.


Omega-neutral production by e-plus e-minus annihilation

Augustin, J.E. ; Benaksas, D. ; Buon, J. ; et al.
Phys.Lett.B 28 (1969) 513-516, 1969.
Inspire Record 56682 DOI 10.17182/hepdata.29065

The reaction e + e − → ω o has been measured by detecting the charged pions of the π + π − π o decay mode of the ω o. A partial decay width of ω o in e + e − : Γ e + e − =0.94±0.18 keV is deduced from this result.

1 data table

FITTED, BACKGROUND SUBTRACTED, PEAK OMEGA CROSS SECTION, CORRECTED FOR UNOBSERVED DECAYS, IS 1.82 +- 0.34 MUB. TABULATED ASSUMING CENTRAL ENERGY IS 782.6 MEV. VACUUM POLARIZATION AND RADIATIVE CORRECTIONS APPLIED.