HEPData Search

From 1.4 million hadronic Z decays collected by the ALEPH detector at LEP, an enriched sample of Z → cc̄ events is extracted by requiring the presence of a high momentum D ∗± . The charm quark forward-backward charge asymmetry at the Z pole is measured to be A FB 0. c = (8.0 ± 2.4) % corresponding to an effective electroweak mixing angle of sin 2 θ W eff = 0.2302 ± 0.0054.

2 data tables

Table 1

Value of SIN2TW(eff) from CQ-quark asymmetries.

Table 2

No description provided.

Production and Decay of the Charged D* Mesons in e+ e- Annihilation at 10-GeV Center-Of-Mass Energy

The ARGUS collaboration Albrecht, H. ; Binder, U. ; Drews, G. ; et al.

Phys.Lett.B 150 (1985) 235-241, 1985.

Inspire Record 204851 DOI 10.17182/hepdata.30448

Using the ARGUS detector at DORIS we have observed the prediction of the charged D ∗ meson in e + e − annihilation at a center of mass energy of 10 GeV. The D ∗ fragmentation function has been measured using the decay channels D ∗+ → D 0 π + and D 0 → K − π + and K − π + π + π − .

2 data tables

Table 1

RESULTS EXTRAPOLATED TO X>O. SYSTEMATIC ERRORS INCLUDED.

Table 2

ERRORS ARE STATISTICAL ONLY.

rivet Analysis
Inclusive production of D0, D+ and D*+ (2010) mesons in B decays and nonresonant e+ e- annihilation at 10.6-GeV

The ARGUS collaboration Albrecht, H. ; Ehrlichmann, H. ; Hamacher, T. ; et al.

Z.Phys.C 52 (1991) 353-360, 1991.

Inspire Record 315059 DOI 10.17182/hepdata.14845

Using the ARGUS detector at thee+e− storage ring DORIS II at DESY, we have measured the inclusive production ofD0,D+ andD*(2010)+ mesons inB decays and in nonresonante+e− annihilation around 10.6 GeV. The inclusive branching ratios forB decays toD0,D+ andD*+ mesons are found to be (52.2±8.2±3.5)%, (27.2±6.3±3.5)% and (34.8±6.0±3.5)% respectively. Thus,D0 andD+ production account for about 70% of the charm produced inB decays, neglectingb→u contributions to the total width. The production cross sections and momentum spectra for continuume+e− annihilation are also presented.

7 data tables

Table 1

Non-resonant inclusive cross sections.

Table 2

Non-resonant inclusive cross sections.

Table 3

Non-resonant inclusive cross sections.

More…

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…

Production of Charmed Mesons in $e^+ e^-$ Annihilation at 10.5-{GeV}

The CLEO collaboration Avery, P. ; Bebek, C. ; Berkelman, Karl ; et al.

Phys.Rev.Lett. 51 (1983) 1139, 1983.

Inspire Record 191835 DOI 10.17182/hepdata.20524

A measurement is presented of the inclusive production of charged D* and neutral D mesons from nonresonant e+e− annihilation in the energy region near the ϒ(4S) resonance. The momentum distribution shows a large contribution at high momenta as expected for heavy quark production. Comparison of the spectrum with several phenomenological models is made. The relative yields of the D* and D mesons indicate that the charm cross section is dominated by the D* contribution.

2 data tables

Table 1

No description provided.

Table 2

No description provided.

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
Continuum charged D* spin alignment at s**(1/2) = 10.5-GeV.

The CLEO collaboration Brandenburg, G. ; Briere, Roy A. ; Ershov, A. ; et al.

Phys.Rev.D 58 (1998) 052003, 1998.

Inspire Record 467595 DOI 10.17182/hepdata.47207

A measurement of the spin alignment of charged D^* mesons produced in continuum e^+ e^- \to c \bar{c} events at \sqrt{s}=10.5 GeV is presented. This study using 4.72 fb^{-1} of CLEO II data shows that there is little evidence of any D^* spin alignment.

4 data tables

Table 1

Systematic errors are not given.

Table 2

Systematic errors are not given.

Table 3

Two decay modes of D0 --> K- PI+ and D0 --> K- PI+ PI0 are combined.

More…

rivet Analysis
A Measurement of D meson production in Z0 hadronic decays

The DELPHI collaboration Abreu, P. ; Adam, W. ; Adye, T. ; et al.

Z.Phys.C 59 (1993) 533-546, 1993.

Inspire Record 356732 DOI 10.17182/hepdata.14375

A study of the fragmentation properties of charm and bottom quarks intoD mesons is presented. From 263 700Z0 hadronic decays collected in 1991 with the DELPHI detector at the LEP collider,D0,D+ andD*+ are reconstructed in the modesK−π+,K−π+K+ andD0π+ followed byD0→K−π+, respectively. The fractional decay widths$\Gamma {{(Z^0\to {D \mathord{\left/ {\vphantom {D {\bar D}}} \right. \kern-\nulldelimiterspace} {\bar D}}X)} \mathord{\left/ {\vphantom {{(Z^0\to {D \mathord{\left/ {\vphantom {D {\bar D}}} \right. \kern-\nulldelimiterspace} {\bar D}}X)} {\Gamma _h }}} \right. \kern-\nulldelimiterspace} {\Gamma _h }}$ are determined, and first results are presented for the production ofD mesons from$c\bar c$ and$b\bar b$ events separately. The average energy fraction ofD*± in charm quark fragmentation is found to be 〈XE(D*)〉c=0.487±0.015 (stat)±0.005 (sys.). Assuming that the fraction ofDs and charm-baryons produced at LEP is similar to that around 10 GeV, theZ0 partial width into charm quark pairs is determined to beΓc/Γh=0.187±0.031 (stat)±0.023 (sys). The probability for ab quark to fragment into$\bar B_s $ orb-baryons is inferred to be 0.268±0.094 (stat)±0.100 (sys) from the measured probability that it fragments into a$\bar B^0 $ orB−.

6 data tables

Table 1

Using full data sample.

Table 2

Using full data sample with proper time > 1 ps to enrich (b bbar) content.

Table 3

Data with Delta(L) > 1.

More…

Inclusive $D$ and $D^*$ Production in $e^+ e^-$ Annihilation at 29-{GeV}

The HRS collaboration Ahlen, S.P. ; Akerlof, C. ; Baranko, G. ; et al.

Phys.Rev.Lett. 51 (1983) 1147, 1983.

Inspire Record 191536 DOI 10.17182/hepdata.20523

Inclusive production of (D0, D¯0) and D± mesons have been observed in e+e− annihilation at 29 GeV. The signals correspond to R values of R(D0+D¯0)=3.25±1.2 and R(D++D−)=1.35±0.6. D*± production is also observed via the process D*+→D0π+ and its charge conjugate. The D and D* production rates are compared.

7 data tables

Table 1

EXTRAPOLATION TO ALL Z.

Table 2

EXTRAPOLATION TO ALL Z.

Table 3

EXTRAPOLATION TO ALL Z.

More…

Date

Collaboration

Subject_areas

Phrases

Reactions Reset

Observables

CM Energies (GeV)

Authors

Production of charmed mesons in Z decays

The Forward - backward asymmetry for charm quarks at the Z pole

Production and Decay of the Charged D* Mesons in e+ e- Annihilation at 10-GeV Center-Of-Mass Energy

rivet Analysis
Inclusive production of D0, D+ and D*+ (2010) mesons in B decays and nonresonant e+ e- annihilation at 10.6-GeV

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

Production of Charmed Mesons in $e^+ e^-$ Annihilation at 10.5-{GeV}

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

rivet Analysis
Continuum charged D* spin alignment at s**(1/2) = 10.5-GeV.

rivet Analysis
A Measurement of D meson production in Z0 hadronic decays

Inclusive $D$ and $D^*$ Production in $e^+ e^-$ Annihilation at 29-{GeV}