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CHARGED HADRON PRODUCTION IN e+ e- ANNIHILATION AT 29-GeV

The TPC/Two Gamma collaboration Aihara, H. ; Alston-Garnjost, M. ; Badtke, D.H. ; et al.

Phys.Rev.Lett. 52 (1984) 577, 1984.

Inspire Record 195994 DOI 10.17182/hepdata.20439

The inclusive production cross sections and mean multiplicities of π±, K±, p, and p¯ in e+e− annihilation at a c.m. energy of 29 GeV have been measured with the time-projection chamber at PEP, using ionization energy loss to separate particle types. On average, 10.7±0.6 π±, 1.35±0.13 K±, and 0.60±0.08 p,p¯ are contained in an annihilation event. The fraction of pions among final-state particles decreases from over 95% at 0.3 GeV/c momentum to about 60% at high momentum; the kaon and proton fractions rise correspondingly.

7 data tables

Table 1

PARTICLE FRACTIONS.

Table 2

PARTICLE FRACTIONS.

Table 3

PARTICLE FRACTIONS.

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A Study of D* Production in High-Energy $\gamma$ p Interactions

Sliwa, K. ; Appel, J.A. ; Biel, J. ; et al.

Phys.Rev.D 32 (1985) 1053-1060, 1985.

Inspire Record 194636 DOI 10.17182/hepdata.23561

We have studied D* production mechanisms using data from a photoproduction experiment at the Fermilab Tagged Photon Spectrometer. A large sample of charged D*’s was selected via the clean signature of the cascade decay D*→D0π+ and subsequently D0→K−π+ or D0→K−π+π0. The cross section for the process γp→(D*++anything)p at an average energy of 105 GeV was measured to be 88±32 nb. Only (11±7)% of D*’s were found to be consistent with being accompanied solely by a D¯* or a D¯; the remaining events contain additional particles. The distribution of the production angle of the D* in the photon-fragmentation-system center of mass is strongly anisotropic and consistent with the form f(θ*)=cos4θ*. We set a limit on the associated-production-process cross section σ(γp→(D¯*−+anything)Λc) x)<60 nb (90% C.L.).

2 data tables

Table 1

No description provided.

Table 2

No description provided.

rivet Analysis
The Total Cross-section for Electron - Positron Annihilation Into Hadron Final States in the $\Upsilon$ Energy Region

The CLEO collaboration Giles, R. ; Hassard, J. ; Hempstead, M. ; et al.

Phys.Rev.D 29 (1984) 1285, 1984.

Inspire Record 193577 DOI 10.17182/hepdata.23768

We report measurements made with the CLEO detector at the Cornell Electron Storage Ring (CESR) of the total cross section for e+e−→hadrons at the ϒ(1S), ϒ(2S), and ϒ(3S), and in the nearby nonresonant continuum. We find R=3.77±0.06 (statistical) ± 0.24 (systematic) for the ratio of the nonresonant hadronic cross section to the cross section for muon-pair production at a center-of-mass total energy W=10.4 GeV. For the leptonic decay widths Γee of the ϒ(1S), ϒ(2S), and ϒ(3S) we obtain 1.30±0.05±0.08, 0.52±0.03±0.04, and 0.42±0.04±0.03 keV, respectively.

1 data table

Table 1

No description provided.

Production and Muonic Decay of Heavy Quarks in e+ e- Annihilation at 34.5-GeV

The TASSO collaboration Althoff, M. ; Braunschweig, W. ; Kirschfink, F.J. ; et al.

Z.Phys.C 22 (1984) 219, 1984.

Inspire Record 194775 DOI 10.17182/hepdata.16252

The production of prompt muons ine+e− annihilation has been studied at centre of mass energies near 34.5 GeV. The measured semi-muonic branching ratios ofb andc quarks areB(b»Xμv) =0.117±0.028±0.01 andB(c→Xμv)=0.082 ±0.012a−0.01+0.02. The fragmentation functions of heavy quarks are hard, <zb>=0.85a−0.12–0.07+0.10+0.02 and <zc> =0.77a−0.07–0.11+0.05+0.03. Limits have been set on flavour changing neutral current decays:B(b→Xµ+µ−) <0.02 andB(b→Xµ+µ− (95% confidence level).

1 data table

Table 1

THE VALUE OF ASYMMETRY WAS DETERMINED USING A SAMPLE OF PROMPT MUONS.

rivet Analysis
Observation of F Meson Production in High-energy $e^+ e^-$ Annihilation

The TASSO collaboration Althoff, M. ; Braunschweig, W. ; Kirschfink, F.J. ; et al.

Phys.Lett.B 136 (1984) 130-134, 1984.

Inspire Record 194774 DOI 10.17182/hepdata.30586

Production of the F meson by e + e − annihilation at high energies has been obsrved in the ϕπ final state with a mass of 1.975 ± 0.009 ± 0.010 GeV and a width consistent with the mass resolution. The yield of F production times branching ratio relative to μ pair production is R F ( x ⩾ 0.3) B (F ± → ϕπ ± ) = 0.061 ± 0.012 ± 0.018.

2 data tables

Table 1

No description provided.

Table 2

CROSS BETWEEN X BRANCHING RATIO DETERMINATION. EXTRAPOLATION BELOW X=0.3 IS USED.

Properties of Charm Jets Produced in $e^+ e^-$ Annihilation Near 34-{GeV}

The TASSO collaboration Althoff, M. ; Braunschweig, W. ; Kirschfink, F.J. ; et al.

Phys.Lett.B 135 (1984) 243-249, 1984.

Inspire Record 194050 DOI 10.17182/hepdata.30600

D ∗± production via e + e − → D ∗± X was studied at CM energies near 34 GeV. The charged particles produced in the hemisphere opposite to that of the D ∗ were used to investigate the fragmentation of charm jets. All spectra studied show a close similarity between the charm jet and the average jet obtained by summing over all quark flavours. The spectra of particles produced in the D ∗ hemisphere were used to study separately first rank and higher rank fragmentation.

2 data tables

Table 1

THE C-JET IS THE JET IN THE HEMISPHERE OPPOSITE TO THAT CONTAINING THE D* MESON. DIVISION IS MADE BY A PLANE PERPENDICULAR TO THE THRUST AXIS.

Table 2

No description provided.

Inclusive $\pi^0$ Production in 360-{GeV} $p p$ Interactions Using the European Hybrid Spectrometer

The EHS-RCBC collaboration Bailly, J.L. ; Bartl, W. ; Bruyant, F. ; et al.

Z.Phys.C 22 (1984) 119, 1984.

Inspire Record 193697 DOI 10.17182/hepdata.2106

The intermediate and forward gamma detectors of EHS are used to reconstructπ°'s produced by 360 GeV/cpp interactions in the Rapid Cycling Bubble Chamber (RCBC). Using thepp forwardbackward symmetry, the inclusiveπ° production cross section is obtainedσπ°=(132±11) mb. The averageπ° multiplicity is determined as a function of the charged particle multiplicity. The (1−x) dependence is given for differentpT regions.

3 data tables

Table 1

No description provided.

Table 2

No description provided.

Table 3

Axis error includes +- 4/4 contribution.

Inelastic and Elastic Photoproduction of J/$\psi$ (3097)

Denby, Bruce H. ; Bharadwaj, V.K. ; Summers, D.J. ; et al.

Phys.Rev.Lett. 52 (1984) 795-798, 1984.

Inspire Record 195929 DOI 10.17182/hepdata.20438

Inelastic and elastic $J/\psi$ photoproduction on hydrogen are investigated at a mean energy of 105 GeV. The inelastic cross section with $E_{\psi} / E_{\gamma}$ < 0.9 is significantly lower than the corresponding result for muoproduction on iron targets, but is consistent with a second-order perturbative QCD calculation.

1 data table

Table 1

No description provided.

rivet Analysis
Charged Multiplicity Distribution in p p Interactions at ISR Energies

The Ames-Bologna-CERN-Dortmund-Heidelberg-Warsaw collaboration Breakstone, A. ; Campanini, R. ; Crawley, H.B. ; et al.

Phys.Rev.D 30 (1984) 528, 1984.

Inspire Record 196601 DOI 10.17182/hepdata.23637

The multiplicities of charged secondaries in proton-proton collisions were determined using the split-field-magnet detector at the CERN Intersecting Storage Rings (ISR). Measurements are presented on multiplicity distributions both for inelastic and non-single-diffractive events at four different energies s=30.4, 44.5, 52.6, and 62.2 GeV. The results reported here represent the first high-statistics measurement of charged multiplicity distributions at ISR energies with a magnetic detector covering nearly the full solid angle.

4 data tables

Table 1

INELASTIC EVENTS.

Table 2

NON-SINGLE-DIFFRACTIVE EVENTS.

Table 3

Moments of the multiplicity distributions for Inelastic events.

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