Differential Three Jet Cross-section in $e^+ e^-$ Annihilation and Comparison With Second Order Predictions of {QCD} and Abelian Vector Theory

The JADE collaboration Bartel, W. ; Cords, D. ; Dietrich, G. ; et al.
Phys.Lett.B 119 (1982) 239-244, 1982.
Inspire Record 180033 DOI 10.17182/hepdata.30830

Differential three-jet cross sections have been measured in e + e − -annihilation at an average CM energy of 33.8 GeV and were compared to first- and second-order predictions of QCD and of a QED-like abelian vector theory. QCD provides a good description of the observed distributions. The inclusion of second-order effects reduced the observed quark-gluon coupling strength by about 20% to α S = 0.16 ± 0.015 (stat.) ± 0.03 (syst.). The abelian vector theory is found to be incompatible with the data.

2 data tables

FIRST ORDER QCD.

SECOND ORDER QCD.


OBSERVATION OF K (1629) MESONS

Karnaukhov, V.M. ; Coca, C. ; Moroz, V.I. ;
JINR-P1-87-559, 1987.
Inspire Record 251892 DOI 10.17182/hepdata.38970

None

1 data table

No description provided.


PRODUCTION OF NEUTRAL STRANGE PARTICLES IN ANTI-P HE-4 ANNIHILATION AT 600-MEV/C. (IN RUSSIAN)

Batusov, Yu.A. ; Balestra, F. ; Barbieri, Riccardo ; et al.
DUBNA JINR - N7-88 (88,REC.FEB.89) 23-31, 1988.
Inspire Record 271238 DOI 10.17182/hepdata.38297

None

5 data tables

No description provided.

No description provided.

No description provided.

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ESTIMATING THE RESONANT PARAMETERS OF A DELTA (33) ISOBAR BASED ON DATA ABOUT PHOTOPRODUCTION OF PI0 MESONS IN A C-12 NUCLEUS

Belousov, A.S. ; Vazdik, Ya.A. ; Malinovsky, E.I. ; et al.
Bull.Lebedev Phys.Inst. 7 (1988) 27-30, 1988.
Inspire Record 271246 DOI 10.17182/hepdata.38326

None

1 data table

No description provided.


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

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

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

No description provided.


Analyzing Power Measurement in Inclusive $\pi^0$ Production at High $\chi_F$

Bonner, B.E. ; Buchanan, J.A. ; Carey, D.C. ; et al.
Phys.Rev.Lett. 61 (1988) 1918, 1988.
Inspire Record 269386 DOI 10.17182/hepdata.2928

The analyzing power AN in inclusive π0 production has been measured with use of the new 185-GeV/c Fermilab polarized proton beam. We obtain the value AN=0.10±0.03 for π0's in the kinematic region 0.2<xF<0.8 and 0.3<pT<1.2 GeV/c. In certain models of particle production this suggests that the spin of the proton is carried by its valence quarks.

7 data tables

No description provided.

No description provided.

Individual polarisation measurements.

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A Model Independent Second Order Determination of the Strong Coupling Constant $\alpha^- s$

Adeva, B. ; Barber, D.P. ; Becker, U. ; et al.
Phys.Rev.Lett. 50 (1983) 2051, 1983.
Inspire Record 189724 DOI 10.17182/hepdata.3086

With use of the MARK-J detector at s=34.7 GeV 21 000 e+e−→hadron events have been collected. By measurement of the asymmetry in angular energy correlations the strong coupling constant αs=0.13±0.01 (statistical)±0.02 (systematic) is determined, in complete second order, and independent of the fragmentation models and QCD cutoff values used.

2 data tables

DATA REQUESTED FROM THE AUTHORS.

No description provided.


Precision Measurement of Electroweak Effects in $e^+ e^- \to \mu^+ \mu^-$ at $\sqrt{s}=29$-{GeV}

Ash, W. ; Band, H. ; Blume, H.T. ; et al.
Phys.Rev.Lett. 55 (1985) 1831, 1985.
Inspire Record 216031 DOI 10.17182/hepdata.3246

A high-statistics measurement has been made of the process e+e−→μ+μ− at s=29 GeV with the MAC detector at the SLAC storage ring PEP. The electroweak forward-backward charge asymmetry for a sample of approximately 16 000 events was measured to be Aμμ=−0.063±0.008±0.002. The ratio of the cross section to the lowest-order QED cross section was measured to be Rμμ=1.01±0.01±0.03. From these results the weak neutral axial-vector and vector couplings are determined to be gAegAμ=0.25±0.03±0.01 and gVegVμ=−0.02±0.03±0.09.

5 data tables

Data are fully corrected, including radiative effects.

Asymmetry determined from a two parameter fit to the angular distribution proportional to R*(1 + cos(theta)**2 + (8/3)*A*cos(theta)). R is then the total ratio relative to the lowest order QED cross section and A is the forward-backward asymmetry.

No description provided.

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Measurement of $e^+ e^- \to \mu^+ \mu^-$ Charge Asymmetry

Adeva, B. ; Barber, D.P. ; Becker, U. ; et al.
Phys.Rev.Lett. 48 (1982) 1701, 1982.
Inspire Record 177308 DOI 10.17182/hepdata.3116

The measurement of the nonelectromagnetic forward-backward charge asymmetry in the reaction e+e−→μ+μ− at s∼34.6 GeV and in the angular region 0<|cosθ|<0.8 is reported. With a systematic error less than 1%, we observe an asymmetry of (-8.1±2.1)%. This is in agreement with the standard electroweak theory prediction of (-7.6±0.6)%. The weak-current coupling constants are also reported.

4 data tables

SEE PRL 55, 665 FOR DISTRIBUTIONS AT 34.6 GEV AND ABOVE.

SEE PRL 55, 665 FOR CROSS SECTION VALUES AND FORWARD BACKWARD ASYMMETRY.

No description provided.

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Electroweak Effects in $e^+ e^- \to \tau^+ \tau^-$ at 29-{GeV}

Fernandez, E. ; Ford, William T. ; Qi, N. ; et al.
Phys.Rev.Lett. 54 (1985) 1620, 1985.
Inspire Record 207555 DOI 10.17182/hepdata.3267

A high-statistics measurement is presented of the cross section for the process e+e−→τ+τ− at s=29 GeV from the MAC detector at PEP. A fit to the angular distribution of our sample of 10 153 events with |cosθ|<0.9 gives an asymmetry Aττ=−0.055±0.012±0.005 from which we find the product of electron and tau axial-vector weak neutral couplings gAegAτ=0.22±0.05.

4 data tables

Data fully corrected up to O(ALPHA**3) radiative effects. Data requested from authors.

Data extrapolated to full acceptance.

No description provided.

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