Richter, Robert
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rivet Analysis
A Search for $\omega \phi$ and $\phi \phi$ Production in the Reactions $\gamma \gamma \to K^+ K^- \pi^+ \pi^- \pi^0$ and $\gamma \gamma \to 2 K^+ 2 K^-$

The ARGUS collaboration Albrecht, H. ; Bockmann, P. ; Glaser, R. ; et al.
Phys.Lett.B 210 (1988) 273-277, 1988.
Inspire Record 260828 DOI 10.17182/hepdata.29918

The reaction γγ→K + K − π + π − π 0 has been observed for the first time, using the ARGUS detector at the e + e − storage ring DORIS II at DESY. The cross section shows an enhancement for W γγ close to 3 GeV/ c 2 . Searches for γγ→ωφ and for γγ→φφ leading to this final state, as well as for γγ→φφ→2K + 2K − , have been performed. The derived upper limits for ωφ and φφ production are compatible with q q q q model predictions.

2 data tables
Table 1

TOPOLOGICAL CROSS SECTION.

Table 2

95 PCT CL UPPER LIMITS.


Observation of the Charmed Baryon $\Lambda(c$) in $e^+ e^-$ Annihilation at 10-{GeV}

The ARGUS collaboration Albrecht, H. ; Bockmann, P. ; Glaser, R. ; et al.
Phys.Lett.B 207 (1988) 109-114, 1988.
Inspire Record 260826 DOI 10.17182/hepdata.29980

Using the ARGUS detector at DORIS II, we have studied the production of the charmed baryon Λ c in e + e − annihilation at centre-of-mass energies near 10 GeV. The Λ c + was seen in the three decay modes pK − π + , Λπ + π − π + and K̄ 0 p, with products of normalized cross section times branching ratio [ R ·Br] of (10.8±1.4±1.2)×10 −3 , 6.6±1.5±0.9)×10 −3 and (6.7±1.4±0.8)×10 −3 respectively. The measured mass for the Λ c was (2283.1±1.7±2.0) MeV/ c 2 . A limit on the decay rates to Λπ + is reported. The fragmentation function of the Λ c was measured.

2 data tables
Table 1

Data requested from authors.

Table 2

No description provided.


OBSERVATION OF psi PRODUCTION IN e+ e- ANNIHILATION AT 29-GeV

Wormser, G. ; Ong, R.A. ; Abrams, G.S. ; et al.
Phys.Rev.D 38 (1988) 1001, 1988.
Inspire Record 260717 DOI 10.17182/hepdata.18617

Inclusive ψ production in e+e− annihilation at 29 GeV has been measured with the Mark II detector. The ψ cross section is found to be 1.1±0.5±0.4 pb. After subtraction of the expected contribution from B decay, an upper limit of 0.02σμμ is obtained for other sources of ψ production.

1 data table
Table 1

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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rivet Analysis
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).


rivet Analysis
Observation of the Charmed Baryon $\Sigma(c$) in $e^+ e^-$ Annihilations

The ARGUS collaboration Albrecht, H. ; Bockmann, P. ; Glaser, R. ; et al.
Phys.Lett.B 211 (1988) 489-492, 1988.
Inspire Record 261672 DOI 10.17182/hepdata.29913

Using the ARGUS detector at the DORIS II storage ring, we have observed the charmed baryons Σ c ++ and Σ c 0 , through their decays to Λ c + π ± . We have measured the mean Σ c −Λ c + mass difference as 167.6±0.3±1.6 MeV/ c 2 . The isospin mass splitting between the Σ c ++ and the Σ c 0 was found to be 1.2±0.7±0.3 MeV/ c 2 . The rate of Λ c + production from Σ c decays was found to be (36±12±11)% of the total rate of Λ c + production. The Σ c χ p spectrum was observed to be similar to that of the Λ c + , with a Peterson function parameter ϵ of 0.29±0.06.

1 data table
Table 1

DATA FROM UPSI(4S) WAS EXCLUDED.


rivet Analysis
Observation of the Orbitally Excited $\Lambda(1520)$ Baryon in $e^+ e^-$ Annihilation

The ARGUS collaboration Albrecht, H. ; Bockmann, P. ; Glaser, R. ; et al.
Phys.Lett.B 215 (1988) 429-434, 1988.
Inspire Record 262415 DOI 10.17182/hepdata.29875

We report the first observation of an orbitally excited baryon, the Λ(1520), in quark and gluon fragmentation. The production rate is found to be (1.15±0.21±0.16)×10 −2 and (0.80±0.17 −0.13 +0.10 )×10 −2 Λ (1520) hyperons per event in direct ϒ decays and in the continuum, respectively. In contrast to the observed situation for ground state baryons, the production of the Λ(1520) in direct ϒ decays shows little or no enhancement with respect to continuum production.

4 data tables
Table 1

Full X range uses extrapolation from fit to dsig/dz distribution.

Table 2

No description provided.

Table 3

UPSI(1S) DECAYS.

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rivet Analysis
First Observation of $\gamma \gamma \to K^*+ K^*$-

The ARGUS collaboration Albrecht, H. ; Bockmann, P. ; Glaser, R. ; et al.
Phys.Lett.B 212 (1988) 528-532, 1988.
Inspire Record 262713 DOI 10.17182/hepdata.29893

The final states K S 0 K S 0 π + π − and K S 0 K ∓ π 0 π ± , produced in two-photon reactions, have been studied using the ARGUS detector at the e + e − storage ring DORIS II at DESY. The reaction γγ→ K ∗+ K ∗− has been observed for the first time. Its cross section is about eight times larger than that for γγ→ K ∗0 K ∗0 , but it has a similar W γγ dependence.

4 data tables
Table 1

No description provided.

Table 2

Topological cross section.

Table 3

Topological cross section.

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rivet Analysis
Inclusive $\phi$ Meson Production in Electron - Positron Interactions in the Energy Region of the $\Upsilon$ Resonances

The ARGUS collaboration Albrecht, H. ; Bockmann, P. ; Glaser, R. ; et al.
Z.Phys.C 41 (1989) 557, 1989.
Inspire Record 262551 DOI 10.17182/hepdata.15528

We report on a high precision measurement of ϕ-meson production in continuum events and in direct decays of the Υ(1S)- and Υ(2S)-mesons. The ratio of the total production rate of ϕ-mesons in direct Υ(1S)- and Υ(2S)-decays over that in continuum events is 1.32±0.08±0.09 and 1.07±0.13±0.11 respectively. This is compatible with the corresponding ratio obtained for lighter mesons, but is appreciably smaller than the relative baryon production rate.

6 data tables
Table 1

PHI meson cross section on the continuum.

Table 2

Differential particle density for PHI mesons in decays of upsilon(1S) and upsilon(2S).

Table 3

No description provided.

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rivet Analysis
Transverse Momentum Distributions of Charged Particles Produced in anti-p p Interactions at s**(1/2) = 630-GeV and 1800-GeV

The CDF collaboration Abe, F. ; Amidei, D. ; Apollinari, G. ; et al.
Phys.Rev.Lett. 61 (1988) 1819, 1988.
Inspire Record 263320 DOI 10.17182/hepdata.20105

Measurements of inclusive transverse-momentum spectra for charged particles produced in proton-antiproton collisions at √2 of 630 and 1800 GeV are presented and compared with data taken at lower energies.

6 data tables
Table 1

No description provided.

Table 2

No description provided.

Table 3

Results of fit to invariant cross section of the form AP0**N/(PT + P0)**N.

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