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

Systematic errors are not given.

Systematic errors are not given.

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

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Measurement of f(c --> D*+ X), f(b --> D*+ X) and Gamma(c anti-c)/Gamma(had) using D*+- mesons.

The OPAL collaboration Ackerstaff, K. ; Alexander, G. ; Allison, John ; et al.
Eur.Phys.J.C 1 (1998) 439-459, 1998.
Inspire Record 447145 DOI 10.17182/hepdata.47409

The production rates of D^*+/- mesons in charm and bottom events at centre-of-mass energies of about 91 GeV and the partial width of primary cc(bar) pairs in hadronic Z^0 decays have been measured at LEP using almost 4.4 million hadronic Z^0 decays collected with the OPAL detector between 1990 and 1995. Using a combination of several charm quark tagging methods based on fully and partially reconstructed D^*+/- mesons, and a bottom tag based on identified muons and electrons, the hadronisation fractions of charm and bottom quarks into D^*+/- mesons have been found to be: f(b -> D^*+ X) = 0.173 +/- 0.016 +/- 0.012 and f(c -> D^*+ X) = 0.222 +/- 0.014 +/- 0.014 The fraction of cc(bar) events in hadronic Z^0 decays, Gamma_cc(bar)/Gamma_had = Gamma(Z^0 -> cc(bar))/Gamma(Z^0 -> hadrons), is determined to be Gamma_cc(bar)/Gamma_had = 0.180 +/- 0.011 +/- 0.012 +/- 0.006 In all cases the first error is statistical, and the second one systematic. The last error quoted for Gamma_cc(bar)/Gamma_had is due to external branching ratios.

3 data tables

No description provided.

No description provided.

The second syst. errors results due to extranal branching ratios. Charge conjugated states are implied. FD is considered as a quark fragmentation fraction. Sqrt(s(E+ E-)) = 91.2 GeV.


Study of Phi(1020), D*+- and B* spin alignment in hadronic Z0 decays.

The OPAL collaboration Ackerstaff, K. ; Alexander, G. ; Allison, John ; et al.
Z.Phys.C 74 (1997) 437-449, 1997.
Inspire Record 440103 DOI 10.17182/hepdata.47515

Measurements of helicity density matrix elements have been made for the φ(1020), D*± and B* vector mesons in multihadronic Z0 decays in the OPAL experiment at LEP. Results for inclusive φ produced with high energy show evidence for production preferentially in the helicity zero state, with ρ00 = 0.54 ± 0.08, compared to the value of 1/3 expected for no spin alignment. The corresponding element for the D*± has a value of 0.40 ± 0.02, also suggesting a deviation from 1/3. The B* result, with ρ00 = 0.36 ± 0.09, is consistent with no spin alignment. Off-diagonal elements have been measured for the f and D* mesons; for the D* the element Re ρ1−1 is non-zero, indicating non-independent fragmentation of the primary quarks.

4 data tables

Helicity density matrices elements. Helicity beam frame is used.

Charge conjugated states are understood.

Helicity density matrices elements. Charge conjugated states are understood.

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

The ALEPH collaboration Buskulic, D. ; Casper, D. ; De Bonis, I. ; et al.
Phys.Lett.B 352 (1995) 479-486, 1995.
Inspire Record 394753 DOI 10.17182/hepdata.47932

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

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

No description provided.


A Study of D*+- production in Z0 decays

The OPAL collaboration Alexander, G. ; Allison, J. ; Allport, P.P. ; et al.
Phys.Lett.B 262 (1991) 341-350, 1991.
Inspire Record 315060 DOI 10.17182/hepdata.9272

In this paper an investigation of the production of D ∗ ± mesons produced in e + e − collisions at energies around the Z 0 pole is presented. Based on 115 D ∗ ± mesons with x D∗  2E D ∗ /E cm > 0.2 the properties of D ∗ mesons produced in the reaction Z 0 → c c are studied. Fixing the yield and the fragmentation function of bottom quarks to the values obtained at LEP using lepton tags, and average energy fraction of the D ∗ ± mesons from primary charmed quarks of 〈x c → D ∗ 〉 = 0.52 ± 0.03 +- 0.01 is found and Γ z 0 →c c = (323 ± 61 ± 35) MeV is determined. The first error is the combined statistical and systematic error from this experiment, and the second the total error from other sources.

2 data tables

FD denotes the fraction of D* mesons from primary charmed quarks, derived from the fit (see text).

No description provided.


Inclusive D*+- production in photon-photon collisions

The TPC/Two-Gamma collaboration Alston-Garnjost, M. ; Avery, R.E. ; Barker, A.R. ; et al.
Phys.Lett.B 252 (1990) 499-504, 1990.
Inspire Record 299662 DOI 10.17182/hepdata.29510

The TPC/Two-Gamma Collaboration has measured the inclusive cross section for production of charmed D ∗± mesons in photon-photon collisions. The reaction utilized was e + e - →e + e - D ∗± X, with D ∗± →D O π +- , D O →K -+ π ± , and either zero or one outgoing e ± detected. The result, σ(e + e - → e + e - D ∗± X) = 74±26±19 pb , is in agreement with the quark parton mo del prediction for e + e - → e + e - c c , combined with a Lund model for the hadronization of the charmed quarks.

2 data tables

No description provided.

No description provided.


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

No description provided.

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


Charm Quark Production and Fragmentation in $e^+ e^-$ Annihilation at 29-{GeV}

Derrick, M. ; Fernandez, E. ; Fries, R. ; et al.
Phys.Lett.B 146 (1984) 261-265, 1984.
Inspire Record 202898 DOI 10.17182/hepdata.51261

The electroweak production asymmetry and the decay fragmentation function for e + e − → c c have been measured at s = 29 GeV using charged D ∗ production over the full kinematic range. The data were taken at PEP using the High Resolution Spectrometer. The measured asymmetry is −0.12 ± 0.08. The total production cross section in units of the point cross section corrected for initial state radiation is R D ∗ = 2.7 ± 0.9 .

2 data tables

ASSUMES SIG(D*+) = SIG(D*0). (EXPT. MEASURES D*+ PRODUCTION ONLY). R VALUE CORRECTED FOR INITIAL STATE RADIATION.

No description provided.


PROPERTIES OF D* PRODUCTION IN e+ e- ANNIHILATION AT 29-GeV

The HRS collaboration Ahlen, S.P. ; Akerlof, C. ; Baranko, G. ; et al.
HRS-CP-83-3, 1983.
Inspire Record 192098 DOI 10.17182/hepdata.13343

None

2 data tables

D* FRAGMENTATION FUNCTION.

R VALUE IS RADIATIVELY CORRECTED (BUT NOT CROSS SECTION).


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

EXTRAPOLATION TO ALL Z.

EXTRAPOLATION TO ALL Z.

EXTRAPOLATION TO ALL Z.

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