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rivet Analysis
Charged Hadron Production in $e^+ e^-$ Annihilation in the $\Upsilon$ and $\Upsilon^\prime$ Region

The LENA collaboration Niczyporuk, B. ; Zeludziewicz, T. ; Chen, K.W. ; et al.
Z.Phys.C 9 (1981) 1, 1981.
Inspire Record 164397 DOI 10.17182/hepdata.1354

Charged hadron production ine+e− annihilation is studied in the 7 to 10 GeV CM energy region and at the Υ (9.46) and Υ′ (10.01) resonances with the LENA detector at DORIS. The statistical moments of the charged multiplicities are studied. The data show KNO scaling behaviour and suggest the presence of long range correlations. An average charged multiplicityrise of Δn(Υ)=0.55±0.19 and Δn(Υ′)=1.26±0.29 over the continuum is observed for the Υ and Υ′ direct decays. The jet structure of the Υ and Υ′ direct decays is investigated using the charged particles. The polar angular distributions of the jet axis behave like 1+α(T) cos2θ with 〈α(T)〉Υ=0.7±0.3 and 〈α(T)〉Υ′=0.6±0.4. The 〈α(T)〉Υ value is in agreement with the QCD vector gluon assignment and excludes scalar gluons by more than four standard deviations.

3 data tables
Table 1

No description provided.

Table 2

No description provided.

Table 3

No description provided.


TOPOLOGY AND CHARGED MULTIPLICITY OF HADRONIC EVENTS IN THE ENERGY REGION OF THE UPSILON AND UPSILON' RESONANCES. (IN GERMAN)

Schwarz, Andreas S. ;
Hamburg Desy - INTERNAL REP. LENA-81-03 (81,REC.SEP.) 178p, 1981.
Inspire Record 171276 DOI 10.17182/hepdata.43836

None

2 data tables
Table 1

OBSERVED, UNCORRECTED, AVERAGE VALUES FOR SPHERICITY AND THRUST.

Table 2

AVERAGE CHARGED MULTIPLICITY - SEE B. NICZYPORUK ET AL., ZP C9, 1 (1981).


Multi-Hadronic Decays and Partial Widths of the J/psi (3100) Resonance Produced in e+ e- Annihilation at ADONE

Bacci, C. ; Baldini-Celio, R. ; Bozzo, M. ; et al.
Phys.Lett.B 58 (1975) 471-474, 1975.
Inspire Record 100017 DOI 10.17182/hepdata.27794

The reactions e + e − → hadrons and e + e + e − →e + e − have been studied at the J/gY (3100) resonance). The relative weights of the topological cross sections for fixed charged multiplicity are σ 2 =(32±5)%, σ 4 =(49±8)%, σ 6 =(18±3)%, and σ 8 =(1±0.6)%. The average pion multiplicities are 〈 n ch 〉=3.8±0.3 and 〈n π o 〉=3.1±0.8 . The decay widths are Γ e =(4.6±0.8) keV, Γ h =(59±24) keV, and Γ =(68±26) keV.

3 data tables
Table 1

CROSS SECTION AROUND RESONANCE.

Table 2

CROSS SECTION JUST BELOW J/PSI.

Table 3

MULTIPLICITY AT J/PSI.


Hadronic Cross-section in $e^+ e^-$ Annihilation From 1.45-{GeV} to 1.80-{GeV}

Esposito, B. ; Marini, A. ; Piano Mortari, Giovanni ; et al.
Lett.Nuovo Cim. 30 (1981) 65-71, 1981.
Inspire Record 170172 DOI 10.17182/hepdata.37368

None

2 data tables
Table 1

CROSS SECTION EXCLUDES ANY CONTRIBUTION FROM TWO-BODY FINAL STATES (PI+ PI- AND K+ K-).

Table 2

CHARGED AND NEUTRAL MULTIPLICITIES.


rivet Analysis
Rapid Growth of Charged Particle Multiplicity in High-Energy e+ e- Annihilations

The TASSO collaboration Brandelik, R. ; Braunschweig, W. ; Gather, K. ; et al.
Phys.Lett.B 89 (1980) 418-422, 1980.
Inspire Record 143691 DOI 10.17182/hepdata.27273

Hadron production by e + e − annihilation has been studied for c.m. energies W between 13 and 31.6 GeV. As a function of 1n W the charged particle multiplicity grows faster at high energy than at lower energies. This is correlated with a rise in the plateau of the rapidity distribution. The cross section s d σ /d x is found to scale within ±30% for x > 0.2 and 5 ⩽ W ⩽ 31.6 GeV.

7 data tables
Table 1

CHARGED PARTICLE MULTIPLICITIES.

Table 2

RAPIDITY DISTRIBUTION.

Table 3

RAPIDITY DISTRIBUTION.

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rivet Analysis
Multiplicity Distributions in e+ e- Annihilations at PETRA Energies

The PLUTO collaboration Berger, Christoph ; Genzel, H. ; Grigull, R. ; et al.
Phys.Lett.B 95 (1980) 313-317, 1980.
Inspire Record 154270 DOI 10.17182/hepdata.27160

Measurements of the charged multiplicities for hadron production in e + e − annihilation in the center of mass energy range 9–32 GeV have been made. The average charged multiplicity has an energy dependence much stronger than ln s and similar to that reported for pp collisions. Quantitative differences are observed in the magnitude of both the average multiplicity 〈 n ch 〉 and the dispersion D ch for e + e − and pp interactions at the same center of mass energy. 〈 n ch 〉 and the ratio 〈 n ch / D ch in e + e − annihilations are significantly larger than in pp collisions and are found to be in overall agreement with QCD predictions. KNO scaling is seen to be satisfied.

1 data table
Table 1

THE FINAL TABLE ENTRY COMBINES THE DATA FROM THE THREE HIGHEST ENERGY BINS.


rivet Analysis
Total Cross-Section for Hadron Production by e+ e- Annihilation at PETRA Energies

The JADE collaboration Bartel, W. ; Canzler, T. ; Cords, D. ; et al.
Phys.Lett.B 88 (1979) 171-176, 1979.
Inspire Record 142874 DOI 10.17182/hepdata.27277

The cross section for the process e + e − → multihadrons has been measured at the highest PETRA energies. We measure R (the total cross section in units of the point-like e + e - → μ + μ - cross section) to be 2.9 ± 0.7, 4.0 ± 0.5, 4.6 ± 0.4 and 4.2 ± 0.6 at s of 22, 27.7, 30 and 31.6 GeV, respectively. The observed average multiplicity, together with existing low energy data, indicate a rapid increase in multiplicity with increasing energy.

2 data tables
Table 1

STATISTICAL ERRORS ONLY. RADIATIVE CORRECTIONS APPLIED AND TAU HEAVY LEPTON CONTRIBUTION SUBTRACTED. AVERAGE VALUE OF R FOR ALL THESE DATA IS 4.14 +- 0.26.

Table 2

AVERAGE CHARGE MULTIPLICITY. ADDITIONAL, SYSTEMATIC ERROR IS ABOUT 1.5.


rivet Analysis
Total Cross-Section for Hadronic Production by e+ e- Annihilation in the Total Center-Of-Mass Energy Range 1.42-GeV - 3.09-GeV

Bacci, C. ; Baldini Celio, R. ; Battistoni, G. ; et al.
Phys.Lett.B 86 (1979) 234-238, 1979.
Inspire Record 141722 DOI 10.17182/hepdata.27311

We report experimental results on the cross section for the reaction e + e − → hadrons as a function of the total c.m. energy in the range W = 1.42–3.09 GeV. The results, combined with those already existing below the charm threshold, clearly indicate a structure for R ( W ) = α ( e + e − → hadrons)/ α ( e + e − → μ + μ − ) in that energy region.

2 data tables
Table 1

THE ENERGY RANGES OF THE NEW DATA AND THE PREVIOUS (REVISED) DATA OVERLAP BETWEEN 1.9 AND 2.0 GEV. RADIATIVE CORRECTIONS HAVE BEEN APPLIED TO ALL DATA. THIS CROSS SECTION EXCLUDES TWO-BODY FINAL STATES.

Table 2

AVERAGE CHARGED AND NEUTRAL MULTIPLICITY. QUOTED ERRORS ARE STATISTICAL ONLY.


rivet Analysis
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
Table 1

No description provided.

Table 2

MEAN CHARGED MULTIPLICITY. ERRORS ARE STATISTICAL ONLY.