Lubelsmeyer, K.
E+ E- Scattering
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rivet Analysis
$K^0$ Production in $e^+ e^-$ Annihilations at 30-{GeV} Center-of-mass Energy

The TASSO collaboration Brandelik, R. ; Braunschweig, W. ; Gather, K. ; et al.
Phys.Lett.B 94 (1980) 91-95, 1980.
Inspire Record 153341 DOI 10.17182/hepdata.27173

Inclusive K 0 -production has been measured in e + e - annihilation at a center of mass energy of about W = 30 GeV. The ratio of K 0 + K 0 production to μ + μ - production is R K 0 = 5.6 ± 1.1 (statist. error) ± 0.8 (system.error) This value is about a factor of three higher than R K 0 at W = 7 GeV. The cross sections ( s / β ) d σ /d x is consistent with a scaling behaviour.

4 data tables
Table 1

No description provided.

Table 2

DIFFERENTIAL CROSS SECTION.

Table 3

INVARIANT CROSS SECTION.

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rivet Analysis
$\Lambda$ Production in $e^+ e^-$ Annihilations at 29-{GeV}: A Comparison With Lund Model Predictions

Baringer, Philip S. ; Abachi, S. ; Beltrami, I. ; et al.
Phys.Rev.Lett. 56 (1986) 1346, 1986.
Inspire Record 17781 DOI 10.17182/hepdata.20257

This paper presents measurements of the inclusive production cross sections of Λ baryons in e+e− annihilations at s=29 GeV. The data sample corresponds to an integrated luminosity of 256 pb−1 collected with the High-Resolution Spectrometer at the SLAC storage ring PEP. Comparisons are made to the predictions of the Lund model. The data are well described with use of a strange-diquark suppression parameter, (usud)(sd), of 0.89 ± 0.10−0.16+0.56, and the measured Λc→Λ+X branching ratio of (23 ± 10)%.

3 data tables
Table 1

No description provided.

Table 2

Rapidity relative to thrust axis.

Table 3

Corrected for unobserved moment regions.


$\Lambda(c$) Production From $e^+ e^-$ Annihilation in the $\Upsilon$ Energy Region

The CLEO collaboration Bowcock, T.J.V. ; Giles, R.T. ; Hassard, J. ; et al.
Phys.Rev.Lett. 55 (1985) 923, 1985.
Inspire Record 214874 DOI 10.17182/hepdata.20302

We have observed Λc baryons in nonresonant e+e− annihilation at energies around s=10.5 GeV through their decay to Λπ+π+π−. We measure the branching fraction to be (2.8 ± 0.7 ± 1.1)%. The momentum spectrum of the Λc is similar to that of charmed mesons, providing a constraint on models of charmed-quark hadronization.

2 data tables
Table 1

No description provided.

Table 2

Data are extrapolated over whole x range using the 'Peterson' formula.


$\Sigma(c$)++ and $\Sigma(c$)0 Production From $e^+ e^-$ Annihilation in the $\Upsilon$ Energy Region

The CLEO collaboration Bowcock, T.J.V. ; Kinoshita, K. ; Pipkin, F.M. ; et al.
Phys.Rev.Lett. 62 (1989) 1240, 1989.
Inspire Record 25467 DOI 10.17182/hepdata.47269

We have observed Σc++ and Σc0 baryons in nonresonant e+e− interactions through their decays to Λc+π± using the CLEO detector. The mass difference M(Σc++)-M(Λc+) is measured to be 167.8±0.4±0.3 MeV; for M(Σc0)-M(Λc+) we find 167.9±0.5±0.3 MeV. Σc decay accounts for (18±3±5)% of Λc+ production.

2 data tables
Table 1

The cross section ratio is multiplied by a factor of 1.5 to account for theunobserved SIGMA/C(2455)+.

Table 2

No description provided.


rivet Analysis
$\pi^0$ Production by $e^+ e^-$ Annihilation at 14-{GeV} and 34-{GeV} Center-of-mass Energy

The TASSO collaboration Brandelik, R. ; Braunschweig, W. ; Gather, K. ; et al.
Phys.Lett.B 108 (1982) 71-76, 1982.
Inspire Record 168232 DOI 10.17182/hepdata.31018

The process e + e − → π 0 + anything has been measured at c.m. energies of 14 and 34 GeV for π 0 energies between 0.5 and 4 GeV. The ratio of π 0 to π ± production for π momenta between 0.5 and 1.5 GeV/ c is measured to be 2 σ ( π 0 )/ [ σ ( π + ) + σ ( π − )] = 1.3 ± 0.4 (1.2 ± 0.4) at 14 (34) GeV. The scaled cross section ( s / μ )d σ /d x when compared with lower energy (4.9–7.4 GeV) π 0 data indicates a substantial scaling violation.

3 data tables
Table 1

COMPARISON OF PI0 WITH CHARGED PION CROSS SECTIONS (SCALED BI 1/S TO SAME ENERGIES).

Table 2

No description provided.

Table 3

No description provided.


$\tau$ Leptonic Branching Ratios and a Search for Goldstone Decay

The MARK-III collaboration Baltrusaitis, R.M. ; Becker, J. ; Blaylock, G. ; et al.
Phys.Rev.Lett. 55 (1985) 1842, 1985.
Inspire Record 215995 DOI 10.17182/hepdata.20284

Pairs of τ leptons produced at s=3.77 GeV have been studied in eμ, ee, and μμ final states. The leptonic branching ratios have been measured to be B(τ→eνν)=(18.2±0.7±0.5)% and B(τ→μνν)=(18.0±1.0±0.6)%. Limits have been set for the two-body decays τ→eG and τ→μG, where G is a light Goldstone boson.

7 data tables
Table 1

No description provided.

Table 2

No description provided.

Table 3

No description provided.

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$\tau$ Production and Decay With the Cello Detector at {PETRA}

The CELLO collaboration Behrend, H.J. ; Criegee, L. ; Dainton, J.B. ; et al.
Phys.Lett.B 222 (1989) 163-172, 1989.
Inspire Record 276859 DOI 10.17182/hepdata.29824

The reaction e + e − → τ + τ − has been studied at centre of mass energies between 14.0 and 46.8 GeV with the CELLO detector at the PETRA e + e − collider. We present results for the cross section σ τ and the charge asymmetry A τ . The results are in good agreement with the standard model. We have also measured the topological decay rates BR 1 , BR 3 and BR 5 for the inclusive decay of the τ lepton into one, three and five charge particles. The results confirm and improve earlier CELLO measurements at other energies. We find for the combined values at all energies BR 1 = (84.9 ± 0.4 ± 0.3)%, BR 3 = (15.0 ± 0.4 ± 0.3)% and BR 5 = (0.16 ± 0.13 ± 0.04)%.

3 data tables
Table 1

No description provided.

Table 2

No description provided.

Table 3

Corrected for radiative effects and background contributions.


A Combined Analysis of the Hadronic and Leptonic Decays of the $\Z^0$

The OPAL collaboration Akrawy, M.Z. ; Alexander, G. ; Allison, J. ; et al.
Phys.Lett.B 240 (1990) 497-512, 1990.
Inspire Record 294808 DOI 10.17182/hepdata.29720

We report on a measurement of the mass of the Z 0 boson, its total width, and its partial decay widths into hadrons and leptons. On the basis of 25 801 hadronic decays and 1999 decays into electrons, muons or taus, selected over eleven energy points between 88.28 GeV and 95.04 GeV, we obtain from a combined fit to hadrons and leptons a mass of M z =91.154±0.021 (exp)±0.030 (LEP) GeV, and a total width of Γ z =2.536±0.045 GeV. The errors on M z have been separated into the experimental error and the uncertainty due to the LEP beam energy. The measured leptonic partial widths are Γ ee =81.2±2.6 MeV, Γ μμ =82.6± 5.8 MeV, and Γ ττ =85.7±7.1 MeV, consistent with lepton universality. From a fit assuming lepton universality we obtain Γ ℓ + ℓ − = 81.9±2.0 MeV. The hadronic partial width is Γ had =1838±46 MeV. From the measured total and partial widths a model independent value for the invisible width is calculated to be Γ inv =453±44 MeV. The errors quoted include both the statistical and the systematic uncertainties.

4 data tables
Table 1

Errors are statistical and point to point systematic luminosity error of 1 pct.

Table 2

Measured values of e+ e- --> e+ e- cross section.

Table 3

Corrected cross section. Corrections are for t-channel effects and loss of acollinear events near the boundary of the acceptance.

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rivet Analysis
A Comparison of jet production rates on the Z0 resonance to perturbative QCD

The DELPHI collaboration Abreu, P. ; Adam, W. ; Adami, F. ; et al.
Phys.Lett.B 247 (1990) 167-176, 1990.
Inspire Record 297698 DOI 10.17182/hepdata.29653

The production rates for 2-, 3-, 4- and 5-jet hadronic final states have been measured with the DELPHI detector at the e + e − storage ring LEP at centre of mass energies around 91.5 GeV. Fully corrected data are compared to O(α 2 s ) QCD matrix element calculations and the QCD scale parameter Λ MS is determined for different parametrizations of the renormalization scale ω 2 . Including all uncertainties our result is α s ( M 2 Z )=0.114±0.003[stat.]±0.004[syst.]±0.012[theor.].

2 data tables
Table 1

Corrected jet rates.

Table 2

Second systematic error is theoretical.


rivet Analysis
A Detailed Study of Strange Particle Production in $e^+ e^-$ Annihilation at High-energy

The TASSO collaboration Althoff, M. ; Braunschweig, W. ; Kirschfink, F.J. ; et al.
Z.Phys.C 27 (1985) 27, 1985.
Inspire Record 205119 DOI 10.17182/hepdata.16068

Results onK0 and Λ production ine+e− annihilation at c.m. energies of 14, 22 and 34 GeV are presented. The shape of theK0 and Λ differential cross sections are very similar to each other and to those of π±,K± and\(p(\bar p)\). Scaling violations are observed forK0 production. We obtain a value for the probability to produce strange quark-antiquark pairs relative to that to produce up or down quark-antiquark pairs of 0.35±0.02±0.05. The value ofRh=σ(e+e-→hX)/σµµ is shown to rise steadily with c.m. energy for all particle species. At 34 GeV we find 1.48±0.05K0 and 0.31±0.03 Λ per event. We have searched for possible Λ polarization. The production ofK0's and Λ's in jets is examined as a function ofpT2 and rapidity and compared to that of all charged particles; the yields in two and three jets are also investigated. Results are presented from events with two baryons\((\Lambda ,\bar \Lambda ,por\bar p)\) observed.

18 data tables
Table 1

No description provided.

Table 2

No description provided.

Table 3

No description provided.

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