Lipeles, Elliot David
[10.0, 12.0]
Max results
Sort by Reverse order

Showing 10 of 84 results

rivet Analysis
Inclusive production of the charmed baryon Lambda(c) from e+ e- annihilations at s**(1/2) = 10.55-GeV

The CLEO collaboration Avery, P. ; Besson, D. ; Garren, L. ; et al.
Phys.Rev.D 43 (1991) 3599-3610, 1991.
Inspire Record 298611 DOI 10.17182/hepdata.22848

We report results on inclusive production of the charmed baryon Λc+ from e+e− annihilations at s=10.5 GeV. Measurements are presented of the inclusive cross section times branching fraction for the continuum production of Λc+ as observed in six different decay modes, and of a new, improved value of the Λc+ mass. The inclusive cross section times the branching fraction into pK−π+ is measured to be 10.0±1.5±1.5 pb summed over all xp. The branching fractions of Λc+ into pK¯0, pK¯0π+π−, Λπ+, Λπ+π−π+, and Ξ−K+π+ relative to that into pK−π+ are measured to be 0.44±0.07±0.05, 0.43±0.12±0.04, 0.18±0.03±0.03, 0.65±0.11±0.12, and 0.15±0.04±0.03, respectively. The Λc+ mass is measured to be 2284.7±0.6±0.7 MeV/c2. The measured momentum distributions for continuum production of Λc+ are compared to analytical fragmentation functions and to other measurements.

8 data tables
Table 1

No description provided.

Table 2

No description provided.

Table 3

No description provided.

More…

Jet fragmentation properties of anti-p p collisions at S**(1/2) = 1.8-TeV

The CDF collaboration Abe, F. ; Amidei, D. ; Apollinari, G. ; et al.
Phys.Rev.Lett. 65 (1990) 968-971, 1990.
Inspire Record 297585 DOI 10.17182/hepdata.19919

The charged-particle fractional momentum distribution within jets, D(z), has been measured in dijet events from 1.8-TeV p¯p collisions in the Collider Detector at Fermilab. As expected from scale breaking in quantum chromodynamics, the fragmentation function D(z) falls more steeply as dijet invariant mass increases from 60 to 200 GeV/c2. The average fraction of the jet momentum carried by charged particles is 0.65±0.02(stat)±0.08(syst).

1 data table
Table 1

No description provided.


Two Jet Differential Cross-Section in anti-p p Collisions at s**(1/2) = 1.8-TeV

The CDF collaboration Abe, F. ; Amidei, D. ; Apollinari, G. ; et al.
Phys.Rev.Lett. 64 (1990) 157, 1990.
Inspire Record 283353 DOI 10.17182/hepdata.19998

The two-jet differential cross section d3σ(p¯p→jet 1+jet 2+X)/dEtdη1dη2, averaged over -0.6≤η1≤0.6, at √s =1.8 TeV, has been measured in the Collider Detector at Fermilab. The predictions of leading-order quantum chromodynamics for most choices of structure functions show agreement with the data.

6 data tables
Table 1

Systematic error contains all known systematic uncertainties, including the effect of uncertainties in the energy scale.

Table 2

Systematic error contains all known systematic uncertainties, including the effect of uncertainties in the energy scale.

Table 3

Systematic error contains all known systematic uncertainties, including the effect of uncertainties in the energy scale.

More…

A MEASUREMENT OF THE TOTAL HADRONIC CROSS-SECTION IN TAGGED gamma gamma REACTIONS

The TPC/Two Gamma collaboration Aihara, H. ; Alston-Garnjost, M. ; Avery, R.E. ; et al.
Phys.Rev.D 41 (1990) 2667, 1990.
Inspire Record 281351 DOI 10.17182/hepdata.22991

We present a measurement of the total cross section for γγ→hadrons, with one photon quasireal and the other a spacelike photon of mass squared −Q2. Results are presented as a function of Q2 and the γγ center-of-mass energy W, with the Q2 range extending from 0.2 to 60 GeV2, and W in the range from 2 to 10 GeV. The data were taken with the TPC/Two-Gamma facility at the SLAC e+e− storage ring PEP, which was operated at a beam energy of 14.5 GeV. The cross section exhibits a gentle falloff with increasing W. Its Q2 dependence is shown to be well described by an incoherent sum of vector-meson and pointlike scattering over most of the observed W range. Agreement at high Q2 is improved if a minimum-pT cutoff (motivated by QCD) is imposed on the pointlike contribution.

4 data tables
Table 1

Errors are statistical only.

Table 2

Errors are statistical only.

Table 3

Errors are statistical only.

More…

$\Sigma(c$)++ and $\Sigma(c$)0 Production From $e^+ e^-$ Annihilation in the $\Upsilon$ Energy Region

The CLEO collaboration Bowcock, T.J.V. ; Kinoshita, K. ; Pipkin, F.M. ; et al.
Phys.Rev.Lett. 62 (1989) 1240, 1989.
Inspire Record 25467 DOI 10.17182/hepdata.47269

We have observed Σc++ and Σc0 baryons in nonresonant e+e− interactions through their decays to Λc+π± using the CLEO detector. The mass difference M(Σc++)-M(Λc+) is measured to be 167.8±0.4±0.3 MeV; for M(Σc0)-M(Λc+) we find 167.9±0.5±0.3 MeV. Σc decay accounts for (18±3±5)% of Λc+ production.

2 data tables
Table 1

The cross section ratio is multiplied by a factor of 1.5 to account for theunobserved SIGMA/C(2455)+.

Table 2

No description provided.


Comparison of Inclusive Fractional Momentum Distributions of Quark and Gluon Jets Produced in $e^+ e^-$ Annihilation

The TASSO collaboration Braunschweig, W. ; Gerhards, R. ; Kirschfink, F.J. ; et al.
Z.Phys.C 45 (1989) 1, 1989.
Inspire Record 277210 DOI 10.17182/hepdata.15299

Inclusive charged particle production ine+e− annihilation into hadrons is studied in terms of the particle fractional momentumxp. Thexp distribution for gluon jets is extracted by comparing two data samples measured in the TASSO detector: nearly symmetric three jet events at centre-of-mass energyW∼35 GeV and two jet events atW∼22 GeV, yielding quark and gluon jets of similar energies (∼11.5 GeV). No significant difference is observed between quark and gluon jets. Monte Carlo models based on parton showers describe the trend and energy variation of the data better than a model with second order matrix element in αs.

3 data tables
Table 1

2 JET data at sqrt(s) = 35 GeV.

Table 2

3 JET data at sqrt(s) = 22 GeV.

Table 3

Gluon jet data at sqrt(s) = 11.5 GeV.


Observation of the Charmed Strange Baryon $\Xi(c$)0

The CLEO collaboration Avery, P. ; Besson, D. ; Garren, L. ; et al.
Phys.Rev.Lett. 62 (1989) 863, 1989.
Inspire Record 267892 DOI 10.17182/hepdata.20029

We present evidence from the CLEO detector for the charmed strange baryon Ξc0. It is seen in nonresonant e+e− annihilations at s of 10.5 GeV through its decay to Ξ−π+. The measured Ξc0 mass is 2471 ± 3 ± 4 MeV/c2.

1 data table
Table 1

Production cross section times branching fraction for the sum of both particle and antiparticle. Error contains both statistics and systematics. X is defined as SQRT(P(P=3)**2/(EBEAM**2-M(P=3)**2)).


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.

More…

High-energy Photoproduction of Large Transverse Momentum $\pi^0$ Mesons: A Quantitative Test of {QCD}

The NA14 collaboration Auge, E. ; Barate, R. ; Bloch, D. ; et al.
Phys.Lett.B 168 (1986) 163-169, 1986.
Inspire Record 227057 DOI 10.17182/hepdata.30278

The first results on inclusive photoproduction of π 0 at transverse momenta up to 4 GeV/ c , using incident γ energies between 50 and 150 GeV are presented. A comparison is made with inclusive π 0 production obtained, in the same experiment, with incident π − . Using the π − data to parametrize the hadronic behaviour of the photon, significant differences are observed in quantitative agreement with QCD Compton scattering and corrections thereof.

2 data tables
Table 1

FC,IC,BC REFER TO FORWARD,INTERMEDIATE AND BACKWARD CALORIMETERS.

Table 2

FC,IC,BC REFER TO FORWARD,INTERMEDIATE AND BACKWARD CALORIMETERS.