Boehm, A.
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Measurement of $e^+ e^- \to \mu^+ \mu^-$: A Test of Electroweak Theories

The Mark-J collaboration Adeva, B. ; Becker, U. ; Becker-Szendy, R. ; et al.
Phys.Rev.Lett. 55 (1985) 665, 1985.
Inspire Record 214607 DOI 10.17182/hepdata.3237

We use the reaction e+e−→μ+μ−, in the Mark J detector at the DESY high-energy e+e− collider PETRA, to test the standard electroweak theory and find good agreement. We also set limits on the parameters of several extended gauge theories.

6 data tables
Table 1

CROSS SECTION MEASUREMENT RELATIVE TO PREDICTED QED CROSS SECTION.

Table 2

FORWARD-BACKWARD ASYMMETRY. THE SYSTEMATIC ERROR IN THE ASYMMETRY IS <0.5 PCT.

Table 3

ANGULAR DISTRIBUTIONS NOT GIVEN IN PAPER. SUPPLIED BY E.DEFFUR.

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rivet Analysis
Study of Hadron and Inclusive Muon Production From Electron Positron Annihilation at 39.79-{GeV} $\le \sqrt{s} \le$ 46.78-{GeV}

The Mark-J collaboration Adeva, B. ; Ansari, S. ; Becker, U. ; et al.
Phys.Rev.D 34 (1986) 681-691, 1986.
Inspire Record 230297 DOI 10.17182/hepdata.23423

We use the reaction e+e−→hadrons, in the Mark J detector at the DESY electron-positron collider PETRA, to determine the hadronic cross section up to 46.78 GeV. The production of a top quark with a charge equal to (2/3) is excluded up to 46.6 GeV with 95% C.L. The observed rise in the cross section at higher energies is consistent with the electroweak prediction for a Z0 mass of 93 GeV. We describe some unusual muon inclusive events.

3 data tables
Table 1

Errors are statistical only.

Table 2

Energy scan of R.

Table 3

Inclusive muon cross section.


The Production and Decay of Tau Leptons

The Mark-J collaboration Adeva, B. ; Ansari, S. ; Becker, U. ; et al.
Phys.Lett.B 179 (1986) 177-182, 1986.
Inspire Record 230298 DOI 10.17182/hepdata.14556

A study of τ-lepton production in the CMS energy region from 14 to 46.8 GeV at PETRA is reported. The cross section, the decay branching ratio into μν ν , and the electroweak parameters are determined with a total integrated luminosity of 115 pb −1 .

4 data tables
Table 1

Total cross section calculated from measured channel cross section assuming BR(tau-mu) = 17.6 pct. SIG(Q=MU) is the QED point cross section.

Table 2

No description provided.

Table 3

No description provided.

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A Measurement of the Strong Coupling Constant $\alpha^- s$ to Complete Second Order

The Mark-J collaboration Adeva, B. ; Anderhub, H. ; Ansari, S. ; et al.
Phys.Lett.B 180 (1986) 181-184, 1986.
Inspire Record 231302 DOI 10.17182/hepdata.6535

The strong interaction coupling constant α s has been measured with a new method, the planar triple energy correlation in the reaction e + e - → hadrons at center-of-mass energies ranging from 14 GeV to 46.78 GeV. A complete second-order perturbative QCD calculation was used. Λ MS = 110 ± 30 −55 +70 MeV is found.

3 data tables
Table 1

No description provided.

Table 2

No description provided.

Table 3

No description provided.


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.


rivet Analysis
Study of Electron - Positron Collisions at the Highest {PETRA} Energy

The Aachen-DESY-Annecy(LAPP)-MIT-NIKHEF-Beijing collaboration Barber, D.P. ; Becker, U. ; Benda, H. ; et al.
Phys.Lett.B 85 (1979) 463-466, 1979.
Inspire Record 141976 DOI 10.17182/hepdata.27332

We report on the results of the study of e + e − collisions at the highest PETRA energy of √ s = 31.57 GeV, using the 4π sr, electromagnetic and calorimetric detector Mark J. Based on 88 hadron events, and an integrated luminosity of 243 nb −1 we obtain R = σ (e + e − → hadrons)/ σ (e + e − → μ + μ − ) = 4.0 ± 0.5 (statistical) ± 6 (systematic). The R value, the measured thrust distribution and average spherocity show no evidence for the production of new quark flavors.

2 data tables
Table 1

CORRECTIONS FOR TWO-PHOTON PROCESSES, TAU HEAVY LEPTON PRODUCTION AND INITIAL STATE RADIATIVE CORRECTIONS HAVE BEEN APPLIED.

Table 2

THRUST DISTRIBUTION (1/N)*DN/DTHRUST AT 31.57 GEV. THESE DATA ARE RATHER DETECTOR DEPENDENT.


Test of Quantum Electrodynamics at {PETRA} Energies

The Aachen-DESY-Annecy(LAPP)-MIT-NIKHEF-Beijing collaboration Barber, D. ; Becker, U. ; Benda, H. ; et al.
Phys.Rev.Lett. 42 (1979) 1110, 1979.
Inspire Record 140093 DOI 10.17182/hepdata.20817

We report on the measurement of the reaction e+e−→e+e− with a large—solid-angle electromagnetic shower detector at center-of-mass energies s=13 and 17 GeV. Comparison of our results with predictions of quantum electrodynamics shows excellent agreement in both the angular distribution and energy dependence. Values of cutoff parameters are also given.

1 data table
Table 1

No description provided.


Study of Electron - Positron Collisions at the Center-of-mass Energies of 27.4-{GeV} and 27.7-{GeV} at {PETRA}

Barber, D.P. ; Becker, U. ; Benda, H. ; et al.
Phys.Rev.Lett. 43 (1979) 901, 1979.
Inspire Record 141542 DOI 10.17182/hepdata.20739

This paper reports on the first results of the study of e+e− collisions at s=27.4 GeV and s=27.7 GeV at PETRA, using the 4π-sr electromagnetic and calorimetric detector MARK-J. We obtain an average R=σ(e+e−→hadrons)σ(e+e−→μ+μ−)=3.8±0.3 (statistical)±0.6 (systematic) and a relative R=1.0±0.2 between the two energies. The R values, the measured thrust distribution, and average spherocity show no evidence for the production of new quark flavors.

2 data tables
Table 1

THE RELATIVE VALUE OF R BETWEEN THESE TWO ENERGIES IS 1.0 +- 0.2.

Table 2

THRUST DISTRIBUTION (1/N)*DN/DTHRUST AT 13, 17 AND 27 GEV. THESE DATA ARE RATHER DETECTOR DEPENDENT.


Measurement of the Relative Total Hadronic Cross-section R at {PETRA}

The Aachen-DESY-Annecy(LAPP)-MIT-NIKHEF-Beijing collaboration Barber, D. ; Becker, U. ; Boehm, A. ; et al.
Phys.Rev.Lett. 42 (1979) 1113, 1979.
Inspire Record 140059 DOI 10.17182/hepdata.3235

We report the first measurement of the ratio R=(σe+e−→hadrons)(σe+e−→μ+μ−) (with negligible τ-lepton contribution) at a center-of-mass energy s=13 GeV and s=17 GeV, from the just finished electron-positron colliding-beam facility PETRA. The detector, MARK-J, has an approximately 4π solid angle and measures γ, e, μ, and charged and neutral hadrons simultaneously. Our results yield R(s=17 GeV)=4.9±0.6 (statistical) ±0.7 (systematic error), and R(s=13 GeV)=4.6±0.5 (statistical) ±0.7 (systematic error). The ratio R(s=17 GeV)R(s=13 GeV) is 1.08±0.18.

2 data tables
Table 1

No description provided.

Table 2

No description provided.


A Test of Universality of Charged Leptons

Barber, D.P. ; Becker, U. ; Benda, H. ; et al.
Phys.Rev.Lett. 43 (1979) 1915, 1979.
Inspire Record 142012 DOI 10.17182/hepdata.20759

Measurements of the reactions e++e−→e++e−, μ++μ−, and τ++τ− at PETRA energies (s12=13,17,27.4,30 and 31.6 GeV) are reported. The results show that these reactions agree well with the predictions of quantum electrodynamics thus determining that all the known charged leptons are pointlike particles to a distance < × 10−16 cm.

2 data tables
Table 1

No description provided.

Table 2

No description provided.