Colley, D.C.
E+ E- --> HADRONS
[10.0, 100.0]
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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.


Observation of Planar Three Jet Events in e+ e- Annihilation and Evidence for Gluon Bremsstrahlung

The JADE collaboration Bartel, W. ; Canzler, T. ; Cords, D. ; et al.
Phys.Lett.B 91 (1980) 142-147, 1980.
Inspire Record 143985 DOI 10.17182/hepdata.6339

Topological distributions of charged and neutral hadrons from the reaction e + e − → multihadrons are studied at √ s of about 30 GeV. An excess of planar events is observed at a rate which cannot be explained by statistical fluctuations in the standard two-jet process. The planar events, mostly consisting of a slim jet on one side and a broader jet on the other, are shown actually to possess three-jet structure by demonstrating that the broader jet itself consists of two collinear jets in its own rest system. Detailed agreement between data and predictions is obtained if the process e + e − →q q ̄ g is taken into account. This strongly suggests gluon bremsstrahlung as the origin of the planar three-jet events. By comparison of the data with the qq̄g-model we obtain a value for the strong coupling constant of α S ( q 2 = 0.17 ± 0.04.

2 data tables
Table 1

THRUST AND PLANARITY DISTRIBUTIONS. FINAL (BETTER) THRUST DISTRIBUTIONS WITH DETECTOR CORRECTIONS TO BE PUBLISHED LATER.

Table 2

No description provided.


Search for Narrow Resonances in $e^+ e^-$ Annihilation at c.m. Energies Between 29.90-{GeV} and 31.46-{GeV}

The JADE collaboration Bartel, W. ; Cords, D. ; Dittmann, P. ; et al.
Phys.Lett.B 91 (1980) 152-154, 1980.
Inspire Record 152290 DOI 10.17182/hepdata.27258

A search for narrow resonances in e + e − annihilation at c.m. energies between 29.90 and 31.46 GeV provides no evidence for the existence of such states. The 90% confidence upper limit on the integrated resonance cross section is 38 nb MeV, significantly below the value expected for the lowest (t,t̄) bound state.

1 data table
Table 1

No description provided.


rivet Analysis
SEARCH FOR NARROW QUARKONIUM STATES AND PAIR PRODUCTION OF NEW HEAVY QUARKS AT c.m. ENERGIES FROM 33-GeV TO 36.7-GeV

The CELLO collaboration Behrend, H.J. ; Chen, Ch. ; Field, J.H. ; et al.
DESY-81-029, 1981.
Inspire Record 166365 DOI 10.17182/hepdata.45222

None

1 data table
Table 1

CONTINUOUS COVERAGE OF THREE ENERGY RANGES (33.00 TO 33.80, 34.00 TO 35.26 AND 36.08 TO 36.72 GEV PLUS SEVEN ADDITIONAL DATA POINTS AROUND 35.7 GEV).


An Analysis of the Charged and Neutral Energy Flow in $e^+ e^-$ Hadronic Annihilation at 34-{GeV}, and a Determination of the {QCD} Effective Coupling Constant

The CELLO collaboration Behrend, H.J. ; Chen, C. ; Fenner, H. ; et al.
Phys.Lett.B 113 (1982) 427-432, 1982.
Inspire Record 177228 DOI 10.17182/hepdata.30921

Using both charged and neutral components, 2600 multihadronic e + e − annihilation events, recorded at 34 GeV by the CELLO detector at PETRA, have been analysed in a calometric approach. The fraction of energy carried by gamma rays is measured to be f γ = (26.0 ± 0.4 (stat) ± 4.0 (syst)%. The neutral energy flow is seen to follow closely the overall energy flow. From the corrected oblateness distribution, a first order determination of α s is performed. The result is α s = 0.16 ± 0.01 (stat) ± 0.03 (syst).

1 data table
Table 1

No description provided.


rivet Analysis
Analysis of the Energy Weighted Angular Correlations in Hadronic $e^+ e^-$ Annihilations at 22-{GeV} and 34-{GeV}

The CELLO collaboration Behrend, H.J. ; Chen, C. ; Fenner, H. ; et al.
Z.Phys.C 14 (1982) 95, 1982.
Inspire Record 12010 DOI 10.17182/hepdata.16413

Measurements of energy weighted angular correlations in electron positron annihilations at c.m. energies of 22 GeV and 34 GeV are presented.

4 data tables
Table 1

ENERGY-ENERGY CORRELATIONS FOR FINAL STATE PARTICLES.

Table 2

ENERGY-ENERGY CORRELATIONS FOR PRIMORDIAL HADRONS.

Table 3

ASSYMETRY IN ENERGY CORRELATIONS FOR FINAL STATE PARTICLES.

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The Influence of Fragmentation Models on the Determination of the Strong Coupling Constant in $e^+ e^-$ Annihilation Into Hadrons

The CELLO collaboration Behrend, H.J. ; Chen, C. ; Fenner, H. ; et al.
Nucl.Phys.B 218 (1983) 269-288, 1983.
Inspire Record 179447 DOI 10.17182/hepdata.8172

Hadronic events obtained with the CELLO detector at PETRA were compared with first-order QCD predictions using two different models for the fragmentation of quarks and gluons, the Hoyer model and the Lund model. Both models are in reasonable agreement with the data, although they do not completely reproduce the details of many distributions. Several methods have been applied to determine the strong coupling constant α S . Although within one model the value of α S varies by 20% among the different methods, the values determined using the Lund model are 30% or more larger (depending on the method used) than the values determined with the Hoyer model. Our results using the Hoyer model are in agreement with previous results based on this approach.

3 data tables
Table 1

DATA CORRECTED WITH HOYER MODEL (ALPHA-S=0.15).

Table 2

DATA CORRECTED WITH LUND MODEL (ALPHA-S=0.25).

Table 3

No description provided.


On the Model Dependence of the Determination of the Strong Coupling Constant in Second Order {QCD} From $e^+ e^-$ Annihilation Into Hadrons

The CELLO collaboration Behrend, H.J. ; Fenner, H. ; Schachter, M.J. ; et al.
Phys.Lett.B 138 (1984) 311-316, 1984.
Inspire Record 195332 DOI 10.17182/hepdata.6634

Hadronic events obtained with the CELLO detector at PETRA are compared with second order QCD predictions using different models for the fragmentation of quarks and gluons into hadrons. We find that the model dependence in the determination of the strong coupling constant persists when going from first to second order QCD calculations.

3 data tables
Table 1

ASYMMETRY FOR DATA CORRECTED WITH IF MODEL (ALPHA-S=0.12).

Table 2

ASSYMETRY FOR DATA CORRECTED WITH SF MODEL (ALPHA-S=0.19).

Table 3

No description provided.


rivet Analysis
Search for New Heavy Quarks in $e^+ e^-$ Collisions Up to 46.78-{GeV} Center-of-mass Energy

The CELLO collaboration Behrend, H.J. ; Burger, J. ; Criegee, L. ; et al.
Phys.Lett.B 144 (1984) 297-301, 1984.
Inspire Record 202783 DOI 10.17182/hepdata.30514

The total e + e − annihilation onto hadron has been measured at CM energies between 33.00 and 36.72 GeV and between 38.66 and 46.78 GeV in steps of 20 and 30 MeV respectively. The average of the ratio R = σ ( e + e − → hadrons )/ σ is 〈 R 〉=3.85±0.12 and 〈 R 〉=4.04±0.10 for the two energy ranges. The systematic error on 〈 R 〉 is 0.31. Both values are consistent with the expectation for the known coloured quarks u, d, s, c and b. No evidence was found for the production of new quarks. If the largest fluctuation in R is interpreted as a narrow resonance, it corresponds to a product of the electronic width and the hadronic branching ratio Γ ee B had >2.9 keV at the 95% confidence level, well below the value expected for the toponium vector ground state with charge 2 3 e . The observed number of aplanar final states rules out the continuum production of a a new heavy flavour with pointlike cross section up to a CM energy of 45.4 GeV for a quarck charge of 1 3 e . and up to 46.6 GeV for 2 3 e at the 95% confidence level.

2 data tables
Table 1

ENERGY SCANS IN 20(30) MEV STEPS.

Table 2

No description provided.


rivet Analysis
Determination of alpha-s and sin**2theta(w) from Measurements of the Total Hadronic Cross-Section in e+ e- Annihilation

The CELLO collaboration Behrend, H.J. ; Burger, J. ; Criegee, L. ; et al.
Phys.Lett.B 183 (1987) 400-411, 1987.
Inspire Record 236981 DOI 10.17182/hepdata.30231

We have measured the total normalized cross section R for the process e + e − → hadrons at centre-of-mass energies between 14.0 and 46.8 GeV based on an integrated luminosity of 60.3 pb −1 . The data are well described by the standard SU(3) c ⊗SU(2) L ⊗U(1) model with the production of the five known quarks. No open production of a sixth quark with charge 2/3 or 1/3 occurs below a centre-of-mass energy of 46.6 or 46.3 GeV, respectively. A fitting procedure which takes the correlations between measurements into account was used to determine the electroweak mixing angle sin 2 θ w and the strong coupling constant α s ( S ) in second-order QCD. We applied this procedure to the CELLO data and in addition included the data from other experiments at PETRA and PEP. Both fits give consistent results. The fit to the combined data yields α s (34 2 GeV 2 ) = 0.165±0.030, and sin 2 θ w = 0.236±0.020. Fixing sin 2 θ w at the world average value of 0.23 yields α s (34 2 GeV 2 ) = 0.169±0.025.

2 data tables
Table 1

No description provided.

Table 2

No description provided.