Stark, Jan
CLEO
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Investigation of the Total Charm Pair Cross-section in Nonresonant $e^+ e^-$ Annihilations at $\sqrt{s}=10$.5-{GeV}

The CLEO collaboration Bowcock, T.J.V. ; Kinoshita, K. ; Pipkin, F.M. ; et al.
Phys.Rev.D 38 (1988) 2679, 1988.
Inspire Record 23509 DOI 10.17182/hepdata.9269

We report results from two new methods for measuring the total production of charmed particles in nonresonant e+e− annihilations at √s =10.5 GeV. The rate for detection of events containing two reconstructed charmed mesons relative to that for events containing one is used to extract information about total charm production independent of decay branching fractions. The value of ΔRcc¯, the total charm-pair cross section normalized to the pointlike μ-pair cross section, is found to be 1.13−0.13+0.17±0.09, under an assumption of limited particle correlations. In an independent analysis the inclusive cross section for e+e−→qq¯→e±X is measured to be 0.293±0.017±0.017 nb. Using measured relative production rates and semileptonic branching fractions of D0 and D+ mesons and estimates of these quantities for Ds and Λc, this is found to correspond to ΔRcc¯=2.07±0.12±0.26. These two measurements are discussed in the context of measurements made by reconstruction of exclusive hadronic decay modes and of theoretical expectations.

3 data tables
Table 1

Charm quarks production cross section (C=CQCQBQR) evaluated from tagged events.

Table 2

Results using method 1).

Table 3

Results using method 2).


Charm Production in Nonresonant e+ e- Annihilations at s**(1/2) = 10.55-GeV

The CLEO collaboration Bortoletto, D. ; Goldberg, M. ; Holmes, R. ; et al.
Phys.Rev.D 37 (1988) 1719, 1988.
Inspire Record 22954 DOI 10.17182/hepdata.23269

We report results on the differential and total cross sections for inclusive production of the charmed particles D*+, D*0, D0, D+, Ds, and Λc in e+e− annihilations at √s=10.55 GeV. Widely used quark fragmentation models are discussed and compared with the measured charmed-particle momentum distributions. This comparison, as well as that with measurements at other center-of-mass energies, shows the need to take QCD corrections into account and their importance for a correct interpretation of the model parameters. The observed rate of D0 and D+ production is compared to the expected total charm production cross section. We measure the probability of a charmed meson being produced as a vector meson and the D*+ decay branching fraction into D0π+.

14 data tables
Table 1

No description provided.

Table 2

No description provided.

Table 3

No description provided.

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A Study of the Decay $B \to \psi$ X

The CLEO collaboration Alam, M.S. ; Katayama, N. ; Kim, I.J. ; et al.
Phys.Rev.D 34 (1986) 3279, 1986.
Inspire Record 230961 DOI 10.17182/hepdata.23447

We have measured the inclusive branching ratio for B→ψX to be (1.09±0.16±0.21)%, and the exclusive branching ratios for B−→ψK− and B¯ ¯0 *0 to be (0.09±0.05)% and (0.41±0.18)%, respectively. The mass difference between neutral and charged B mesons is 1.1±2.1 MeV, while the difference between the mass of Υ(4S) and twice the mean B-meson mass is 18.5±3.0 MeV. The ψ momentum distribution implies a substantial two-body decay (in agreement with direct measurements), but also some combination of B→ψX with MX>1.5 GeV, and B→ψ’X.

2 data tables
Table 1

No error for cross-section given in text.

Table 2

No description provided.


Observation of the Decay $B \to$ F X

The CLEO collaboration Haas, P. ; Hempstead, M. ; Jensen, T. ; et al.
Phys.Rev.Lett. 56 (1986) 2781, 1986.
Inspire Record 228879 DOI 10.17182/hepdata.20235

We present evidence for inclusive F-meson production in B-meson decay. The product branching fraction B(B→FX)B(F+→φπ+) is measured to be 0.0038±0.010. The F momentum spectrum indicates the presence of a large component of two-body final states in the decay B→FX.

3 data tables
Table 1

No description provided.

Table 2

DATA SAMPLE CONSISTED OF 77 1/PB. DATA TAKEN ON THE PEAK OF THE UPSI(10575).

Table 3

CONTINUUM DATA SAMPLE CONSISTED OF 36 1/PB. ENERGY JUST BELOW THE UPSI(10575).


rivet Analysis
A Measurement of the Direct Photon Spectrum From the $\Upsilon$ (1s)

The CLEO collaboration Csorna, S.E. ; Mestayer, M.D. ; Panvini, R.S. ; et al.
Phys.Rev.Lett. 56 (1986) 1222, 1986.
Inspire Record 220652 DOI 10.17182/hepdata.20260

We have observed decays of the ϒ(1S) into hadronic final states containing high-energy photons. These are interpreted as coming from the decay ϒ(1S)→γ+gluon+gluon. We compare the shape of the observed photon energy spectrum with several theoretical predictions and deduce the value of the strong-coupling constant αs and the QCD scale parameter ΛMS― (MS― denotes the modified minimal-subtraction scheme) associated with each prediction.

2 data tables
Table 1

DATA TAKEN ON THE PEAK OF THE UPSI(9460).

Table 2

DATA TAKEN ON THE PEAK OF THE UPSI(9460).


Inclusive $\phi$ Production in $B$ Meson Decay

The CLEO collaboration Bortoletto, D. ; Chen, A. ; Garren, L. ; et al.
Phys.Rev.Lett. 56 (1986) 800, 1986.
Inspire Record 218314 DOI 10.17182/hepdata.20228

We have measured the inclusive branching ratio for B→φX to be 0.023±0.006±0.005. The momentum distribution of the φ mesons is compared with that expected from the cascade decays B→F→φ and B→D→φ. .AE

3 data tables
Table 1

DATA SAMPLE CONSISTED OF 30.4 1/PB. DATA TAKEN ON THE PEAK OF THE UPSI(10575).

Table 2

CONTINUUM DATA SAMPLE CONSISTED OF 12.8 1/PB. ENERGY JUST BELOW THE UPSI(10575).

Table 3

69970 B BBAR EVENTS.


$\Lambda(c$) 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.


Observation of New Structure in the e+ e- Annihilation Cross-Section Above B anti-B Threshold

The CLEO collaboration Besson, D. ; Green, J. ; Namjoshi, R. ; et al.
Phys.Rev.Lett. 54 (1985) 381, 1985.
Inspire Record 205667 DOI 10.17182/hepdata.20359

Measurements of the e+e− cross section above BB¯ threshold are reported. Structures are observed which could be the ϒ(5S) and ϒ(6S) resonances. The masses and widths are given and compared with various potential-model predictions. Average charged multiplicities and inclusive lepton yields are also presented.

1 data table
Table 1

No description provided.


rivet Analysis
Inclusive Hadron Production in Upsilon Decays and in Nonresonant electron-Positron Annihilation at 10.49-GeV

The CLEO collaboration Behrends, S. ; Chadwick, K. ; Gentile, T. ; et al.
Phys.Rev.D 31 (1985) 2161, 1985.
Inspire Record 205668 DOI 10.17182/hepdata.23589

We report measurements of single-particle inclusive spectra and two-particle correlations in decays of the Υ(1S) resonance and in nonresonant annihilations of electrons and positrons at center-of-mass energy 10.49 GeV, just below BB¯ threshold. These data were obtained using the CLEO detector at the Cornell Electron Storage Ring (CESR) and provide information on the production of π, K, ρ, K*, φ, p, Λ, and Ξ in quark and gluon jets. The average multiplicity of hadrons per event for upsilon decays (compared with continuum annihilations) is 11.4 (10.5) pions, 2.4 (2.2) kaons, 0.6 (0.5) ρ0, 1.2 (0.8) K*, 0.6 (0.4) protons and antiprotons, 0.15 (0.08) φ, 0.19 (0.07) Λ and Λ¯, and 0.016 (0.005) Ξ− and Ξ¯ +. We have also seen evidence for η and f0 production. The most significant differences between upsilon and continuum final states are (1) the inclusive energy spectra fall off more rapidly with increasing particle energy in upsilon decays, (2) the production of heavier particles, especially baryons, is not as strongly suppressed in upsilon decays, and (3) baryon and antibaryon are more likely to be correlated at long range in upsilon decay than in continuum events.

36 data tables
Table 1

No description provided.

Table 2

No description provided.

Table 3

VALUES AT X = 0.10 ARE ACTUALLY AP RATES DOUBLED.

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Hyperon Production in $e^+ e^-$ Interactions in the $\Upsilon$ Region

The CLEO collaboration Alam, M.S. ; Csorna, S.E. ; Garren, L. ; et al.
Phys.Rev.Lett. 53 (1984) 24, 1984.
Inspire Record 200712 DOI 10.17182/hepdata.20410

We report measurements from the CLEO detector of the rate of Ξ and Λ production in e+e− interactions in the upsilon region. Hyperon production from the decay of the ϒ(1s) is compared with continuum e+e− data. The ratio of the production rates of Λ (and Λ―) to K0 (and K―0) on the ϒ(1s) is 0.21 ± 0.03, much larger than in the continuum, 0.07 ± 0.01. The ratios of the production rates of the Ξ and Λ are comparable, 0.10±0.02 [ϒ(1S)] and 0.07 ± 0.02 (continuum). We discuss some implications of the data for gluon and quark fragmentation models.

2 data tables
Table 1

CONTINUUM IS ECM 10.38 TO 10.64 GEV.

Table 2

No description provided.