Alam, M.S.
E+ E- Scattering
DSIG/DZ
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rivet Analysis
Multiplicities of pi0, eta, K0 and of charged particles in quark and gluon jets.

The OPAL collaboration Abbiendi, G. ; Ackerstaff, K. ; Ainsley, C. ; et al.
Eur.Phys.J.C 17 (2000) 373-387, 2000.
Inspire Record 529898 DOI 10.17182/hepdata.49911

We compared the multiplicities of pizero, eta, Kzero and of charged particles in quark and gluon jets in 3-jet events, as measured by the OPAL experiment at LEP. The comparisons were performed for distributions unfolded to 100% pure quark and gluon jets, at an effective scale Qjet which took into account topological dependences of the 3-jet environment. The ratio of particle multiplicity in gluon jets to that in quark jets as a function of Qjet for pizero, eta and Kzero was found to be independent of the particle species. This is consistent with the QCD prediction that the observed enhancement in the mean particle rate in gluon jets with respect to quark jets should be independent of particle species. In contrast to some theoretical predictions and previous observations, we observed no evidence for an enhancement of eta meson production in gluon jets with respect to quark jets, beyond that observed for charged particles. We measured the ratio of the slope of the average charged particle multiplicity in gluon jets to that in quark jets, C, and we compared it to a next-to-next-to-next-to leading order calculation. Our result, C=2.27+-0.20(stat+syst),is about one standard deviation higher than the perturbative prediction.

3 data tables
Table 1

No description provided.

Table 2

Symmetric on energy jets.

Table 3

No description provided.


rivet Analysis
$\eta$ and $\eta^\prime$ Production in $e^+ e^-$ Annihilation at 29-{GeV}: Indications for the $D(s$)+- Decays Into $\eta \pi^\pm$ and $\eta^\prime \pi^\pm$

Wormser, G. ; Abrams, G.S. ; Amidei, D. ; et al.
Phys.Rev.Lett. 61 (1988) 1057, 1988.
Inspire Record 261194 DOI 10.17182/hepdata.20080

η production has been investigated by the Mark II collaboration at the SLAC e+e− storage ring PEP. η particles are reconstructed by their γγ decay mode. The η fragmentation function has been measured and found to be in good agreement with the Lund-model prediction. η′ production has been measured for the first time in high-energy e+e− annihilation. There is evidence at the 3σ level for Ds± decay into ηπ± and η′π±.

4 data tables
Table 1

Numerical values supplied by G.Wormser.

Table 2

Z = 0.0 point extrapolated using LUND fragmentation model.

Table 3

Z = 0.0 point extrapolated using LUND fragmentation model.

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LAMBDA AND K0 PRODUCTION IN THE UPSILON REGION

Green, J. ; Hicks, R.G. ; Sannes, F. ; et al.
PRINT-83-0866, 1983.
Inspire Record 192219 DOI 10.17182/hepdata.12780

None

5 data tables
Table 1

NUMBER OF K0S PER EVENT IN THE UPSILON REGION.

Table 2

NUMBER OF ANTI(LAMBDA)S PER EVENT IN THE UPSILON REGION. FOR UPSI(4S) RESULTS SEE 'A'.

Table 3

DSIG/DP DISTRIBUTIONS FOR K0 AND (ANTI) LAMBDA PRODUCTION AT THE UPSILON RESONANCES.

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Inclusive Charged $D^*$ Production in $e^+ e^-$ Annihilations at $W=10$.4-{GeV}

The CLEO collaboration Bebek, C. ; Hassard, J. ; Hempstead, M. ; et al.
Phys.Rev.Lett. 49 (1982) 610, 1982.
Inspire Record 178490 DOI 10.17182/hepdata.20565

A measurement is presented of inclusive charged D*(2010) production from nonresonant e+e− annihilation in the center-of-mass energy (W) range 10.2 GeV<W<10.6 GeV. Charged D* mesons are identified by the decays D*+→D0π+→K−π+π+ and the charge conjugate mode. It is found that 40 ± 7 ± 13% of the charm quarks from the process e+e−→cc¯ result in D* mesons with z>0.7 (z=2EW, where E is the D* energy).

2 data tables
Table 1

No description provided.

Table 2

No description provided.


$D$ Meson Production in $e^+ e^-$ Annihilation at Ecm Between 3.8-{GeV} and 6.7-{GeV}

Coles, M.W. ; Abrams, G.S. ; Blocker, C.A. ; et al.
Phys.Rev.D 26 (1982) 2190, 1982.
Inspire Record 178099 DOI 10.17182/hepdata.23943

The Mark II detector at SPEAR has been used to study D-meson production in e+e− annihilation at center-of-mass energies between 3.8 and 6.7 GeV. The neutral and charged D mesons are identified from their K∓π± and K∓π±π± decay modes. Measurements of RD and of the inclusive differential cross section s dσdz are presented. The quasi-two-body cross sections σDD¯, σD*D¯, and σD*D¯* are derived from an overall fit to the D recoil spectra. No evidence was found for the associated production of charmed mesons and charmed baryons.

4 data tables
Table 1

No description provided.

Table 2

No description provided.

Table 3

THE DIFFERENTIAL SCALING CROSS SECTION FOR NEUTRAL AND CHARGED D'S. DEFINITION OF Z IS 2*E(P=3)/SQRT(S).

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Hadron Production by $e^+ e^-$ Annihilation at Center-of-mass Energies Between 2.6-{GeV} and 7.8-{GeV}. Part 2. Jet Structure and Related Inclusive Distributions

Hanson, G. ; Alam, M.S. ; Boyarski, A. ; et al.
Phys.Rev.D 26 (1982) 991, 1982.
Inspire Record 170499 DOI 10.17182/hepdata.38162

We present results on the jet structure observed in multihadronic events produced by e+e− annihilation in the Mark I magnetic detector at SPEAR. The evidence for jet structure and the jet-axis angular distribution are reported. We give inclusive distributions of the hadrons in Feynman x, rapidity, and transverse momentum relative to the jet axis.

19 data tables
Table 1

Observed particle PT with respect to jet axis for events with three or more detected charged particles.

Table 2

No description provided.

Table 3

No description provided.

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