Wang, J.C.
ALPHAS
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A Measurement of Strong Coupling Constant $\alpha_s$ to Second Order for 14-{GeV} $\le \sqrt{s} \le$ 46.78-{GeV}

The MARK-J collaboration Adeva, B. ; Becker, U. ; Becker-Szendy, R. ; et al.
Phys.Rev.Lett. 54 (1985) 1750, 1985.
Inspire Record 208007 DOI 10.17182/hepdata.20386

Using the Mark-J detector at the high-energy e+e− collider PETRA, we compare the data from hadron production with the complete second-order QCD calculation over the energy region 22 to 46.78 GeV. We determine the QCD parameter Λ=100±30−45+60 MeV which yields the strong-coupling constant αs=0.12±0.02 for s=44 GeV.

2 data tables
Table 1

No description provided.

Table 2

Axis error includes +- 0.0/0.0 contribution (DUE TO FRAGMENTATION MODEL).


Determination of $\alpha_s$ in First and Second Order {QCD} From $e^+ e^-$ Annihilation Into Hadrons

The TASSO collaboration Althoff, M. ; Braunschweig, W. ; Kirschfink, F.J. ; et al.
Z.Phys.C 26 (1984) 157, 1984.
Inspire Record 203143 DOI 10.17182/hepdata.16210

None

1 data table
Table 1

No description provided.


Experimental Test of the Flavor Independence of the Quark - Gluon Coupling Constant

The TASSO collaboration Althoff, M. ; Braunschweig, W. ; Kirschfink, F.J. ; et al.
Phys.Lett.B 138 (1984) 317-324, 1984.
Inspire Record 199470 DOI 10.17182/hepdata.6609

Reconstruction of charged D ∗ 's produced inclusively in e + e −. annihilation at CM energies near 34.4 GeV is accomplished in the decay modes D ∗ + → D 0 π + → K − gp + π 0 π + and D ∗ + → D 0 π + → K − gp + π − π + π + and their charge conjugates. Using these and previously reported D ∗ + → D 0 π + → K − gp + π + and D ∗ + → D 0 π + → K − gp + π + + missing π 0 channels we present evidence for hard gluon bremsstrahlung from charm quarks and show that the ratio of the quark-gluon coupling constant of charm quarks to the coupling constant obtained in the average hadronic event, α s c α rms = 100 ± 0.20 ± 1.20 . Our result provides evidence that the quark-gluon coupling constant is independent of flavor.

3 data tables
Table 1

No description provided.

Table 2

No description provided.

Table 3

No description provided.


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
Table 1

DATA REQUESTED FROM THE AUTHORS.

Table 2

No description provided.


rivet Analysis
A Measurement of Sigma(tot) (e+ e- ---> Hadrons) for CM Energies Between 12.0-GeV and 36.7-GeV

The TASSO collaboration Brandelik, R. ; Braunschweig, W. ; Gather, K. ; et al.
Phys.Lett.B 113 (1982) 499-508, 1982.
Inspire Record 176887 DOI 10.17182/hepdata.6666

The ration R = σ (e + e − → hadrons) σ μμ was measured between 12.0 and 36.7 GeV c.m. energy W with a precision of typically ± 5.2%. R is found to be constant with an average R = 4.01 ± 0.03 (stat) ± (syst.) for W ⩾ 14 GeV. Quarks are found to be point-like, the mass parameter describing a possible quark form-factor being larger than 186 GeV. Fits including QCD corrections and a weak neutral-current contribution are presented.

4 data tables
Table 1

DATA OF RUNPERIOD 1.

Table 2

DATA OF RUNPERIOD 2.

Table 3

R MEASURED IN SCANNING MODE.

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Measurement of Energy Correlations in $e^+ e^- \to$ Hadrons

Schlatter, D. ; Abrams, G.S. ; Amidei, D. ; et al.
Phys.Rev.Lett. 49 (1982) 521, 1982.
Inspire Record 171070 DOI 10.17182/hepdata.20563

Energy correlations have been measured with the MARK II detector at the PEP storage ring (Stanford Linear Accelerator Center) at c.m. energy of 29 GeV and are compared to first-order QCD predictions. Fragmentation processes are significant and limit the precision with which the first-order strong-coupling constant can be determined.

2 data tables
Table 1

CORRELATION IS THE ENERGY WEIGHTED CROSS SECTION FOR OBSERVING THE ENERGY E1 IN THE SOLID ANGLE DOMEGA1 AND THE ANGLE E2 IN THE SOLID ANGLE DOMEGA2.SUMMED OVER ALL PAIRS OF PARTICLES IN DOMEGA1 AND DOMEGA2 AND ALL EVENTS.

Table 2

MEASUREMENT OF THE STRONG COUPLING CONSTANT.


rivet Analysis
Comparison of e+ e- Annihilation with QCD and Determination of the Strong Coupling Constant

The TASSO collaboration Brandelik, R. ; Braunschweig, W. ; Gather, K. ; et al.
Phys.Lett.B 94 (1980) 437-443, 1980.
Inspire Record 153511 DOI 10.17182/hepdata.5489

We have analyzed 1113 events of the reaction e + e − → hadrons at CM energies of 12 and 30 GeV in order to make a detailed comparison with QCD. Perturbative effects can be well separated from effects depending on the quark and gluon fragmentation parameters to yield a reliable measurement of the coupling constant α S . At 30 GeV, the result is α S = 0.17 ± 0.02 (statistical) ± 0.03 (systematic). QCD model predictions, using the fragmentation parameters determined along with α S , agree with both gross properties of the final states and with detailed features of the three-jet states.

7 data tables
Table 1

No description provided.

Table 2

No description provided.

Table 3

No description provided.

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Tests of Quantum Chromodynamics and a Direct Measurement of the Strong Coupling Constant $\alpha_S$ at $\sqrt{s}=30$-{GeV}

Barber, D.P. ; Becker, U. ; Benda, H. ; et al.
Phys.Lett.B 89 (1979) 139-144, 1979.
Inspire Record 143680 DOI 10.17182/hepdata.6483

We report the measurement of the reaction e + + e − → hadronic jets at a center-of-mass energy √ s =30 GeV using the MARK-J detector at PETRA. By measuring the energy and angular distribution of both neutrals and charged particles we were able to isolate unambiguously the three-jet events in a kinematic region where the backgrounds from q q and phase space contributions and other processes are small. Various comparisons of the data with quantum chromodynamics were made. The relative yield of three-jet events and the shape distribution of the events enable us to determine α s = 0.23 ± 0.02 (statistical error) with a systematic error of ± 0.04.

2 data tables
Table 1

OBLATENESS AND THRUST DISTRIBUTIONS FOR NARROW AND BROAD JETS AT 30 GEV. THESE DATA ARE SOMEWHAT ANALYSIS AND DETECTOR DEPENDENT.

Table 2

No description provided.