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Inclusive D0 and $D^+$ Production in $e^+ e^-$ Annihilation at 29-{GeV}

Derrick, M. ; Fernandez, E. ; Fries, R. ; et al.
Phys.Rev.Lett. 53 (1984) 1971, 1984.
Inspire Record 202899 DOI 10.17182/hepdata.51258

We have observed inclusive production of D0 and D+ mesons, and their charge conjugates, in e+e− annihilation at 29 GeV on the basis of a data sample of 106 pb−1. These signals correspond to R values of R(D0+D―0)=1.8±0.5 and R(D++D−)=1.2±0.4. Taking the D+ and D0 data together, we measure a charge asymmetry of A=−0.08±0.12 for charmed quarks. A comparison of R(D+D―) with R(D*+D―*) obtained via the process D*+→D0π+ gives a DD* ratio of 1.0−0.2+0.3, indicating that direct D* production dominates over direct D production.

4 data tables
Table 1

No description provided.

Table 2

EXTRAPOLATED TO ALL Z.

Table 3

No description provided.

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PROMPT ELECTRON PRODUCTION IN ELECTRON - POSITRON ANNIHILATIONS AT 29-GeV

Koop, Dale E. ;
CALT-68-1149, 1984.
Inspire Record 201707 DOI 10.17182/hepdata.50118

None

7 data tables
Table 1

Axis error includes +- 9/9 contribution (DUE TO UNCERTAINTIES IN DETECTION EFFICIENCIES//DUE TO UNCERTAINTIES IN LUMINOSITY//DUE TO UNCERTAINTIES IN BACKGROUND SUBSTRUCTIONS).

Table 2

Axis error includes +- 9/9 contribution (DUE TO UNCERTAINTIES IN DETECTION EFFICIENCIES//DUE TO UNCERTAINTIES IN LUMINOSITY//DUE TO UNCERTAINTIES IN BACKGROUND SUBSTRUCTIONS).

Table 3

Axis error includes +- 9/9 contribution (DUE TO UNCERTAINTIES IN DETECTION EFFICIENCIES//DUE TO UNCERTAINTIES IN LUMINOSITY//DUE TO UNCERTAINTIES IN BACKGROUND SUBSTRUCTIONS).

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Observation of a New Charmed Meson.

The ARGUS collaboration Albrecht, H. ; Binder, U. ; Harder, G. ; et al.
Phys.Rev.Lett. 56 (1986) 549, 1986.
Inspire Record 222219 DOI 10.17182/hepdata.20225

Using the ARGUS detector at the DORIS II e+e− storage ring at DESY, we have obtained evidence for a new charmed resonance which decays into D*±(2010)π∓. The observed mass and width are 2420±6 MeV/c2 and 70±21 MeV/c2, respectively. The fragmentation function is found to be hard, as expected for a state containing a leading charm quark produced by nonresonant e+e− annihilation.

2 data tables
Table 1

No description provided.

Table 2

Estimated production cross section obtained by comparison with observed D*(2010) production rate.


Charged $D^*$ Production in $e^+ e^-$ Annihilation at 29-{GeV} and a Limit on D0 - Anti-d0 Mixing

Yamamoto, H. ; Atwood, W.B. ; Baillon, P. ; et al.
Phys.Rev.Lett. 54 (1985) 522-525, 1985.
Inspire Record 205132 DOI 10.17182/hepdata.20325

We have studied inclusive D*± production using the DELCO detector at PEP. Our technique involved kaon identification in the momentum range above 3.2 GeV/c using a threshold gas Čerenkov counter. This leads to a model-independent upper limit on D0−D¯0 mixing of 8.1% (90% confidence level). We also have measured the charm fragmentation function, which peaks at x≡PD*(Ebeam2−MD*2)12 of 0.56±0.06(stat.), and the total cross section for D* production, σ(D*±)=0.140±0.021(stat.)±0.032(syst.) nb (x>0.3, with radiative correction).

2 data tables
Table 1

No description provided.

Table 2

SYSTEMATIC ERROR DOES NOT INCLUDE THE UNCERTAINTY ON THE BRANCHING RATIOS USED.


$\Lambda(c$) 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.


rivet Analysis
Production of $\phi$ and F (1970) $\to \phi \pi$ in $e^+ e^-$ Annihilation at 29-{GeV}

Derrick, M. ; Fernandez, E. ; Fries, R. ; et al.
Phys.Rev.Lett. 54 (1985) 2568, 1985.
Inspire Record 213242 DOI 10.17182/hepdata.20340

Data from the high-resolution spectrometer at PEP have been used to study the inclusive production of φ mesons and F± mesons decaying into φπ±. Fragmentation functions and cross sections are presented and compared to existing data. The total φ cross section at 29 GeV is 40±6 pb. The observed F signal in the region z>0.4, given the assumption that R(F)[R(F)+R(D)]=0.15, corresponds to an F→φπ branching ratio of (3.3±1.1)%. The measured F mass is 1963±3±3 MeV/c2.

5 data tables
Table 1

No description provided.

Table 2

No description provided.

Table 3

WITH THE FOLLOWING ANGLE CUTS ON THE DECAY REGIONS. PHI DECAY - ABS(COS(THETA)) >0.5.

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rivet Analysis
Test of spin dependence in charm-quark fragmentation to D*.

The TPC/Two-Gamma collaboration Aihara, H. ; Alston-Garnjost, M. ; Avery, R.E. ; et al.
Phys.Rev.D 43 (1991) 29-33, 1991.
Inspire Record 316132 DOI 10.17182/hepdata.22830

We have measured the polarization of D*, the energy dependence of the polarization, and the spin-density matrix of D* in e+e− annihilation at a center-of-mass energy of 29 GeV using the Time Projection Chamber detector at the SLAC storage ring PEP. In 147 pb−1 of data we see no strong evidence for polarization, alignment, or final-state interactions in this fragmentation process.

2 data tables
Table 1

Polarization is the factor alpha(z) in the expression d width (D*-->D pi)/domega = C(1+alpha(z)cos(theta)**2).

Table 2

Spin density matrices for D* --> D0 pi+.


rivet Analysis
Observation of the D*0 (2459) in e+ e- Annihilation

The ARGUS collaboration Albrecht, H. ; Bockmann, P. ; Glaser, R. ; et al.
Phys.Lett.B 221 (1989) 422-426, 1989.
Inspire Record 268577 DOI 10.17182/hepdata.29827

Using the ARGUS detector at the DORIS II storage ring at DESY, we have observed a charmed meson of mass (2455±3±5) MeV/c2, decaying to D + π − . The natural width of this state is determined to be (15 +13+5 −10−10 ) MeV c 2 . The fragmentation function is hard, as expected for a leading charmed particle from nonresonant e + e − annihilation. Analysis of the decay angular distribution supports the hypothesis that the observed state is an L =1 excited charmed meson with spin-parity 2 + .

2 data tables
Table 1

Corrected to zero momentum using fragmentation function of Peterson et al., PR D29 (83) 105.

Table 2

Data read from graph.


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.


Evidence for F* Meson Production in $e^+ e^-$ Annihilation at 10-{GeV} Center-of-mass Energy

The ARGUS collaboration Albrecht, H. ; Drews, G. ; Harder, G. ; et al.
Phys.Lett.B 146 (1984) 111-115, 1984.
Inspire Record 202781 DOI 10.17182/hepdata.30513

Using the ARGUS detector at DORIS we have obtained evidence for a resonance which decays into an F meson and a photon. The observed mass is 2109 ± 9 ± 7 MeV, which is 144 ± 9 ± 7 MeV greater than the F meson mass. Its properties are consistent with those of the F ∗ meson with J P = 1 − .

1 data table
Table 1

No description provided.