Stark, Jan
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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
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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The Real Part of the Proton - anti-Proton Elastic Scattering Amplitude at the Center-Of-Mass Energy of 546-GeV

The UA4 collaboration Bernard, Denis ; Bozzo, M. ; Braccini, P.L. ; et al.
Phys.Lett.B 198 (1987) 583, 1987.
Inspire Record 249671 DOI 10.17182/hepdata.30077

Proton-antiproton elastic scattering was measured at the CERN SPS Collider at the centr-of-mass energy s =546 GeV in the Coulomb interference region. The data provide information on the phase of the hadronic amplitude in the forward direction. The conventional analysis gives for the ratio ϱ of the real to the imaginary part of the hadronic amplitude the result ϱ =0.24±0.04.

2 data tables
Table 1

Axis error includes +- 0.025/0.025 contribution (Normalisation was fixed using a previous UA4 measurement of the total cross section: sig(name=tot)*(1 + alpha**2)).

Table 2

Best estimate of alpha(rho).


The Cross-section of Diffraction Dissociation at the {CERN} {SPS} Collider

The UA4 collaboration Bernard, Denis ; Bozzo, M. ; Braccini, P.L. ; et al.
Phys.Lett.B 186 (1987) 227-232, 1987.
Inspire Record 235895 DOI 10.17182/hepdata.30212

Single diffraction dissociation was measured in the reaction p¯p→p¯X at the centre-of-mass energy √ s = 546 GeV. The mass M of the system X was deduced from the pseudorapidity distribution of the observed charged tracks. The cross section of single diffraction dissociation for M 2 /s⩽0.05isσ sd =9.4 ± 0.7 mb. Comparison to the ISR data shows that σ sd increases with energy less fast than the total and the elastic cross sections.

1 data table
Table 1

No description provided.


rivet Analysis
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).


Large T Elastic Scattering at the {CERN} {SPS} Collider at $\sqrt{s}=630$-{GeV}

The UA4 collaboration Bernard, Denis ; Bozzo, M. ; Braccini, P.L. ; et al.
Phys.Lett.B 171 (1986) 142-144, 1986.
Inspire Record 227143 DOI 10.17182/hepdata.30263

Proton-antiproton elastic scattering was measured at the centre-of-mass energy s = 630 GeV in the four-momentum transfer range 0.7 ⩽ − t ⩽ 2.2 GeV 2 . The new data confirm our previous results at s = 546 GeV on the presence of a break in the t -distribution at − t ≃ 0.9 GeV 2 which is followed by a shoulder, and extend the momentum transfer range to larger values. The t -dependence of the differential cross section beyond the break is discussed.

1 data table
Table 1

Errors contain statistics and acceptance uncertainty.


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).


rivet Analysis
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.