Caplan, H.S.
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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
Table 1

DATA REQUESTED FROM THE AUTHORS.

Table 2

No description provided.


Fragmentation of Heavy Quarks Produced in $e^+ e^-$ Annihilation

Fernandez, E. ; Ford, William T. ; Read, Alexander L. ; et al.
Phys.Rev.Lett. 50 (1983) 2054, 1983.
Inspire Record 189417 DOI 10.17182/hepdata.20548

Identification of muons in hadronic events from e+e− annihilation observed in the MAC detector at the storage ring PEP provides flavor tagging of heavy primary quarks. A sample enriched in events from bb¯ production is obtained and the b-quark fragmentation function is inferred from the momentum spectrum of the muons. The b quark is found to fragment predominantly with high values of z, with 〈zb〉=0.8±0.1, and to have an over-all semimuonic branching fraction of (15.5−2.9+5.4)%.

2 data tables
Table 1

No description provided.

Table 2

No description provided.


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

Fernandez, E. ; Ford, William T. ; Read, Alexander L. ; et al.
Phys.Rev.Lett. 50 (1983) 1238, 1983.
Inspire Record 188749 DOI 10.17182/hepdata.20560

A measurement of the cross section for production of collinear muon pairs based upon a sample of about 3000 events observed in the MAC detector at the storage ring PEP is presented. From the angular asymmetry Aμμ=0.076±0.018 the axial-vector weak neutral coupling is found to be given by gAegAμ=0.31±0.08.

2 data tables
Table 1

Data on non-collinearity and angular distribution.

Table 2

Asymmetry measurement based on extrapolation of number of events to 4 PI acceptance.


rivet Analysis
Search for Top Quark and a Test of Models Without Top Quark at the Highest {PETRA} Energies

Adeva, B. ; Barber, D.P. ; Becker, U. ; et al.
Phys.Rev.Lett. 50 (1983) 799, 1983.
Inspire Record 182337 DOI 10.17182/hepdata.20549

With a PETRA energy scan in ≤30-MeV steps, the continuum production of open top quark up to 38.54 GeV is excluded. Over regions of energy scan from 29.90 to 38.63 GeV limits are set on the product of hadronic branching ratio and electronic width BhΓee for toponium to be less than 2.0 keV at the 95% confidence level. By a search for flavor-changing neutral currents in b decay, models without a top quark are excluded.

4 data tables
Table 1

MEASUREMENT OF R IN ENERGY SCAN FROM SQRT(S) = 29.9 TO 3.146 AND 33.0 TO 36.72.

Table 2

MEASUREMENT OF R IN THE RANGE SQRT(S) 37 TO 38.63 GEV.

Table 3

THRUST DISTRIBUTION FOR EVENTS IN THE RANGE SQRT(S) 37.94 TO 38.63 AND 38.54 TO 38.63.

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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
Table 1

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

Table 2

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

Table 3

No description provided.

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rivet Analysis
Measurement of Hadron Production and Three Jet Event Properties at {PETRA} {MIT}

Barber, D.P. ; Becker, U. ; Bei, G.D. ; et al.
Phys.Lett.B 108 (1982) 63-66, 1982.
Inspire Record 166369 DOI 10.17182/hepdata.31009

We have performed a high statistics measurement of the production rate and the energy flow pattern of hadron events between √ s =33 and 36.7 GeV. The data show no evidence for the production of a new quark with charge 2 3 e . Planar events in e + e − →hadrons are shown to have three well separated jets. The production rate and the shape of three-jet events are compared with many models and we find that only the QCD model can explain the data.

1 data table
Table 1

ENERGY SCAN WITH 7077 HADRON EVENTS.


Experimental Study of Electroweak Parameters at {PETRA} Energies (12-{GeV} $< E_{CMS} <$ 36.7-{GeV})

The MARK-J collaboration Barber, D.P. ; Becker, U. ; Bei, G.D. ; et al.
Phys.Rev.Lett. 46 (1981) 1663, 1981.
Inspire Record 164675 DOI 10.17182/hepdata.3303

We have performed a high-statistics measurement of Bhabha scattering and of the production of hadrons in electron-positron annihilation at PETRA energies (12 GeV<~s<~36.7 GeV). Combining the results with measurements of μ+μ− and τ+τ− production enables us to compare our results with electroweak theory. We find sin2θw=0.27±0.08. This is in good agreement with the value obtained from neutrino experiments which were carried out in entirely different kinematic regions.

5 data tables
Table 1

No description provided.

Table 2

No description provided.

Table 3

ASYMMETRY WAS USED.

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PRODUCTION RATIOS FOR HADRONS PRODUCED IN MUON PROTON INELASTIC SCATTERING AT 219-GEV

Proudfoot, J. ; Booth, N.E. ; Quirk, T.W. ; et al.
Phys.Rev.D 24 (1981) 2012-2015, 1981.
Inspire Record 172688 DOI 10.17182/hepdata.24051

Results on kaon, pion, and proton production in muon-proton scattering are presented for 10.2(z=Phadν) are fπ=0.764±0.028, fK=0.187±0.042, and fp=0.049±0.013. The K±π± ratios as a function of z and pT2 are presented: The ratios increase with z, and with pT2 for z<0.3.

1 data table
Table 1

No description provided.


Unique Solution for the Weak Neutral Current Coupling Constants in Purely Leptonic Interactions

The Mark-J collaboration Barber, D.P. ; Becker, U. ; Berghogff, G. ; et al.
Phys.Lett.B 95 (1980) 149-153, 1980.
Inspire Record 154136 DOI 10.17182/hepdata.6235

By combining results from the MARK-J at PETRA on Bhabha scattering, μ + μ - and τ + τ - production with recent world data from neutrino-electron scattering experiments, we determine unique values for the leptonic weak neutral current coupling constants g V and g A in the framework of electroweak models containing a single Z 0 . In contrast to previous analyses, we only use data from purely leptonic interactions, and therefore avoid the inherent uncertainties resulting from the use of hadronic targets. From the MARK-J data alone in the context of the standard SU(2) ⊗ U (1) model of Glashow, Weinberg and Salam, we find sin 2 θ W =0.24±0.11.

3 data tables
Table 1

No description provided.

Table 2

No description provided.

Table 3

No description provided.


Search for the Production of a New Quark Flavor at the Highest {PETRA} Energies

Barber, D.P. ; Becker, U. ; Benda, H. ; et al.
Phys.Rev.Lett. 44 (1980) 1722, 1980.
Inspire Record 152616 DOI 10.17182/hepdata.20702

This paper reports the results of a study of hadron production in e+e− collisions at c.m. system energies of 33, 35, and 35.8 GeV. Production of a new quark flavor has been sought. The measured values of the total cross section, the thrust distributions, and the study of inclusive muon production show no evidence for the production of a new charge-23e quark near threshold. In addition, during an energy scan in the region 29.9<~s<~31.6 GeV, no hadron resonance indicating the existence of a bound state composed of charge-23e quarks has been found.

3 data tables
Table 1

No description provided.

Table 2

ENERGY SCAN IN 20 MEV STEPS.

Table 3

THRUST DISTRIBUTION (1/N)*DN/DTHRUST AT 29.9 TO 31.6 AND 35 GEV. THESE DATA ARE RATHER DETECTOR DEPENDENT.