Hyperon Production in $e^+ e^-$ Annihilation at 10-{GeV} Center-of-mass Energy

The ARGUS collaboration Albrecht, H. ; Binder, U. ; Bockmann, P. ; et al.
Z.Phys.C 39 (1988) 177, 1988.
Inspire Record 251097 DOI 10.17182/hepdata.1697

The production cross sections for the Λ, Σ0, Ξ−, Σ0 (1385), Ξ0 (1530) and Ω− hyperons have been measured, both in the continuum and in direct ϒ decays. Baryon rates in direct ϒ decays are enhanced by a factor of 2.5 or more compared to the continuum. Such a large baryon enhancement cannot be explained by standard fragmentation models. The strangeness suppression for baryons and mesons turns out to be the same. A strong suppression of spin 3/2 states is observed.

23 data tables

Hyperon rates per multihadronic event in direct UPSILON decays.

Hyperon rates per multihadronic event in the continuum.

LAMBDA spectrum (1/SIG(had))*D(SIG)/D(X) for UPSILON (1S) direct decays, with X = P/Pmax.

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Evidence for chain - like production of strange baryon pairs in jets

The OPAL collaboration Acton, P.D. ; Alexander, G. ; Allison, John ; et al.
Phys.Lett.B 305 (1993) 415-427, 1993.
Inspire Record 353460 DOI 10.17182/hepdata.48367

The production dynamics of baryon-antibaryon pairs are investigated using hadronic Z 0 decays, recorded with the OPAL detector, which contain at least two identified Λ baryons. The rapidly difference for Λ Λ pairs shows the correlations expected from models with a chain-like production of baryon-antibaryon pairs. If the baryon number of a Λ is compensated by a Λ , the Λ is found with a probability of 53% in an interval of ±0.6 around the Λ rapidity. This correlation strength is weaker than predicted by the Herwig Monte Carlo and the Jetset Monte Carlo with a production chain of baryon-antibaryon, and stronger than predicted by the UCLA model. The observed rapidity correlations can be described by the Jetset Monte Carlo with a dominant production chain of baryon-meson-antibaryon, the popcorn mechanism. In addition to the short range correlations, one finds an indication of a correlation of Λ Λ pairs in opposite hemispheres if both the Λ and the Λ have large rapidities. Such long range correlations are expected if the primary quark flavours are compensated in opposite hemispheres and if these quarks are found in energetic baryons. Rates for simultaneous baryon and strangeness number compensation for Λ Λ , Ξ − Ξ + and Ξ − Λ ( Λ + Λ ) are measured and compared with different Monte Carlo models.

17 data tables

No description provided.

Opposite and same baryon number invariant PI P mass distribuition for additional LAMBDA(LAMBDABAR) candidates in events with one identified LAMBDA(LAMBDABAR). CT.= Data read from plot.

Opposite and same baryon number invariant PI P mass distribuition for additional LAMBDA(LAMBDABAR) candidates in events with one identified XI-(XIBAR+). CT.= Data read from plot.

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A Measurement of strange baryon production in hadronic Z0 decays

The OPAL collaboration Acton, P.D. ; Alexander, G. ; Allison, J. ; et al.
Phys.Lett.B 291 (1992) 503-518, 1992.
Inspire Record 336771 DOI 10.17182/hepdata.29036

The production of the octet and decuplet baryons Λ, Ξ − , Σ (1385) ± , Ξ(1530) 0 and Ω − and the corresponding antibaryons has been measured in a sample of 485 000 hadronic Z 0 decays. Results on differential and integrated cross sections are presented. The differential cross section of Λ baryons is found to be softer than the one predicted by the Jetset and Herwig Monte Carlo generators. The measured decuplet yields are found to disagree with the simple diquark picture where only one tuning parameter for spin 1 diquarks is used. Comparisons of the momentum spectra for Λ and Ξ − with the predictions of an analytical QCD formula are also presented.

13 data tables

No description provided.

No description provided.

No description provided.

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Study of inclusive Lambda production in e+ e- annihilations at 29-GeV

The HRS collaboration Geld, T.L. ; Neal, H. ; Akerlof, C. ; et al.
Phys.Rev.D 45 (1992) 3949-3954, 1992.
Inspire Record 339573 DOI 10.17182/hepdata.22726

Cross sections are presented for the inclusive production of Λ hyperons in electron-positron annihilations at s=29 GeV based on the full 291-pb−1 sample of data taken in the High Resolution Spectrometer experiment at the SLAC e+e− storage ring PEP. These results, and the associated correlation analyses, are consistent with the Lund model predictions with the strange diquark suppression ratio δ fixed at 0.59±0.10±0.18, as compared to the standard Lund value of 0.32. The Λ multiplicity has been found to be 0.182±0.020 per event. The opposite-strangeness multiplicity 〈nΛΛ¯〉 has been measured to be 0.046±0.020, whereas the like-strangeness multiplicity 〈nΛΛ+Λ¯Λ¯〉 is 0.009±0.028. A strong correlation is found between Λ's and Λ¯'s; when one is found in an event, the other is found in the same event with a probability that exceeds 50%.

4 data tables

No description provided.

Extrapolate to full z interval using Lund fit.

No description provided.

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Neutral kaon and lambda production in electron - positron annihilation at 29-GeV and the Z boson resonance

Fordham, C. ;
SLAC-0374, 1990.
Inspire Record 300503 DOI 10.17182/hepdata.18797

None

26 data tables

No description provided.

No description provided.

No description provided.

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STUDY OF p p AND LAMBDA LAMBDA PRODUCTION IN e+ e- ANNIHILATION AT 10-GeV CENTER-OF-MASS ENERGY

The ARGUS collaboration Albrecht, H. ; Ehrlichmann, H. ; Glaser, R. ; et al.
Z.Phys.C 49 (1991) 349-354, 1991.
Inspire Record 295621 DOI 10.17182/hepdata.15433

None

8 data tables

Ratio per multihadron event for continuum data.

Ratio per multihadron event for continuum data.

Ratio per multihadron event for continuum data.

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Strange Baryon Production in e+ e- Annihilation

The TASSO collaboration Braunschweig, W. ; Gerhards, R. ; Kirschfink, F.J. ; et al.
Z.Phys.C 45 (1989) 209, 1989.
Inspire Record 266893 DOI 10.17182/hepdata.15283

The production of strange baryons ine+e− annihilation has been studied at centre of mass energies of 34.8 GeV and 42.1 GeV, using the TASSO detector at DESY. Inclusive cross-sections have been obtained forΛ0 andΞ− production and an upper limit has been placed upon the production rate of Σ*±(1385). We measure theΛ0 multiplicity per event to be\(\begin{gathered}\hfill \\0.218_{ - 0.011}^{ + 0.011}\pm 0.021 \hfill \\ \end{gathered} \) and\(0.256_{ - 0.029}^{ + 0.030}\pm 0.025\) at\(\sqrt s=34.8\) and 42.1 GeV respectively. The Ξ− multiplicity per event is found to be\(0.014_{ - 0.003}^{ + 0.003}\pm 0.004\) at\(\sqrt s=34.8 GeV\). An investigation has been made of the extent to whichΛ0 are produced in pairs. TheΛ0 cross-section has been studied as a function of event sphericity.

24 data tables

No description provided.

No description provided.

No description provided.

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Inclusive Strange Particle Production in $e^+ e^-$ Annihilation

The CELLO collaboration Behrend, H.J. ; Criegee, L. ; Field, J.H. ; et al.
Z.Phys.C 46 (1990) 397-404, 1990.
Inspire Record 283026 DOI 10.17182/hepdata.15225

We present an analysis of strange particle production frome+e− annihilation into multihadronic final states. The experiment was performed with the CELLO detector at the PETRA storage ring at DESY, the data was taken at a centre of mass energy of 35 GeV with an integrated luminosity of 86 pb−1. The particlesKS0,K*± and Λ have been identified by their characteristic decays, and differential cross sections for their production have been obtained. From a comparison ofKS0 andK*± rates the Lund vector meson suppression parameterV/(V+P)S has been determined.

6 data tables

Errors are statistical only.

Errors are statistical only.

Errors are statistical only.

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Observation of Octet and Decuplet Hyperons in $e^+ e^-$ Annihilation at 10-{GeV} Center-of-mass Energy

The ARGUS collaboration Albrecht, H. ; Binder, U. ; Bockmann, P. ; et al.
Phys.Lett.B 183 (1987) 419-424, 1987.
Inspire Record 236982 DOI 10.17182/hepdata.30227

Results on hyperon production are reported for data accumulated at 10 GeV centre-of-mass energy with the ARGUS detector. Signals for both the octet states Λ, Σ 0 and Ξ − and the decuplet states Σ ± (1385), Ξ 0 (1530) and Ω − are observed 1 (references to a specific state are to be interpreted as also implying the charge conjugate state), some for the first time in e + e − annihilation. Baryon rates from γ dir (1S) decays are enhanced by a factor of about 3 over the continuum.

2 data tables

No description provided.

No description provided.


Hadron Production in $e^+ e^-$ Annihilation at $\sqrt{s}=29$-{GeV}

Derrick, M. ; Fernandez, E. ; Fries, R. ; et al.
Phys.Rev.D 35 (1987) 2639, 1987.
Inspire Record 215848 DOI 10.17182/hepdata.23381

Data from the High Resolution Spectrometer at the SLAC storage ring PEP have been used to study the inclusive production of baryons and mesons. Time-of-flight measurements are used to identify the charged hadrons. Neutral hadrons are identified from effective-mass peaks associated with their decay into two charged particles. Cross sections and other inclusive production characteristics are presented for π±, K±, and K0 (K¯0) mesons, and for the baryons (antibaryons) p (p¯) and Λ (Λ¯). The ratio of the inclusive cross section to the point cross section for the K0 and K¯0 mesons is R(K0,K¯0)=6.15±0.13±0.25, and for Λ and Λ¯, R(Λ,Λ¯)=0.846±0.036±0.085. The neutral-hadron differential cross sections are compared with the predictions of the Lund string model.

8 data tables

Charged particle fractions. Errors contain systematic uncertainties.

Charged particle invariant cross sections. Errors contain systematic uncertainties.

Charged particle invariant cross sections. Errors contain systematic uncertainties.

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