Greene, A.F.
E+ E- Scattering
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Determination of A(b)(FB) using jet charge measurements in Z decays.

The ALEPH collaboration Barate, R. ; Buskulic, D. ; Decamp, D. ; et al.
Phys.Lett.B 426 (1998) 217-230, 1998.
Inspire Record 468671 DOI 10.17182/hepdata.49559

An improved measurement of the forward-backward asymmetry in Z →b b ̄ decays is presented, based on a sample of 4.1 million hadronic Z decays collected by ALEPH between 1991 and 1995. Data are analysed as a function of polar angle of the event axis and b purity. The event tagging efficiency and mean b -jet hemisphere charge are measured directly from data. From the measured forward-backward jet charge asymmetry, the b quark asymmetry at s =m Z is determined to be: A b FB =0.1017±0.0038(stat.)±0.0032(syst.). In the context of the Standard Model this corresponds to a value of the effective weak mixing angle of sin 2 θ W eff =0.23109±0.00096.

3 data tables
Table 1

Only statistical errors are given for sqrt(s) = 89.43 and 92.97 GeV.

Table 2

The combination of the data on and off peak of Z-boson.

Table 3

The combination of the data on and off peak of Z-boson.


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.

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Measurements of the structure of quark and gluon jets in hadronic Z decays.

The ALEPH collaboration Barate, R. ; Buskulic, D. ; Decamp, D. ; et al.
Eur.Phys.J.C 17 (2000) 1-18, 2000.
Inspire Record 467225 DOI 10.17182/hepdata.49549

An experimental investigation of the structure of identified quark and gluon jets is presented. Observables related to both the global and internal structure of jets are measured; this allows for test

6 data tables
Table 1

The measured jet broadening distributions (B) in quark and gluon jets seperately.

Table 2

Measured distributions of -LN(Y2), where Y2 is the differential one-subjet rate, that is the value of the subjet scale parameter where 2 jets appear from the single jet.

Table 3

The mean subjet multiplicity (-1) for gluon jets and quark jets for different values of the subject resolution parameter Y0.

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rivet Analysis
Measurements of the meson photon transition form factors of light pseudoscalar mesons at large momentum transfer.

The CLEO collaboration Gronberg, J. ; Hill, T.S. ; Kutschke, Robert K. ; et al.
Phys.Rev.D 57 (1998) 33-54, 1998.
Inspire Record 446031 DOI 10.17182/hepdata.47203

Using the CLEO~II detector, we have measured the differential cross sections for exclusive two-photon production of light pseudoscalar mesons $\pi^0$, $\eta$, and $\eta^{\prime}$. From our measurements we have obtained the form factors associated with the electromagnetic transitions $\gamma^*\gamma$ $\to$ meson. We have measured these form factors in the momentum transfer ranges from 1.5 to 9, 20, and 30 GeV$^2$ for $\pi^0$, $\eta$, and $\eta^{\prime}$, respectively, and have made comparisons to various theoretical predictions.

10 data tables
Table 1

The results of PI0 --> GAMMA GAMMA analysis assuming Br(PI0-->2GAMMA)=0.99.

Table 2

The results of ETA --> GAMMA GAMMA analysis assuming Br(ETA-->2GAMMA)=0.39.

Table 3

The results of ETA --> 3PI0 analysis assuming Br(ETA-->3PI0)*Br(PI0-->2GAM MA)**3 = 0.31.

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rivet Analysis
Measurement of the total cross section for e+ e- --> hadrons at s**(1/2) = 10.52-GeV.

The CLEO collaboration Ammar, R. ; Baringer, Philip S. ; Bean, A. ; et al.
Phys.Rev.D 57 (1998) 1350-1358, 1998.
Inspire Record 445351 DOI 10.17182/hepdata.47132

Using the CLEO detector at the Cornell Electron Storage Ring, we have made a measurement of R=sigma(e+e- ->hadrons)/sigma(e+e- ->mu+mu-) =3.56+/-0.01+/-0.07 at ECM=10.52 GeV. This implies a value for the strong coupling constant of alpha_s(10.52 GeV)=0.20+/-0.01+/-0.06, or alpha_s(M_Z)=0.13+/-0.005+/-0.03.

2 data tables
Table 1

Corrected for background and radiactive effects.

Table 2

Value of ALPHAS, the strong coupling constant, from the measurement of R. CT,= ALPHAS also given evolved to the Z0 mass.


rivet Analysis
First observation of inclusive B decays to the charmed strange baryons Xi/c0 and Xi/c+.

The CLEO collaboration Barish, B. ; Chadha, M. ; Chan, S. ; et al.
Phys.Rev.Lett. 79 (1997) 3599-3603, 1997.
Inspire Record 442910 DOI 10.17182/hepdata.47081

Using data collected in the region of the Upsilon(4S) resonance with the CLEO II detector operating at the Cornell Electron Storage Ring CESR, we present the first observation of B mesons decaying into the charmed strange baryons Xi_c0 and Xi_c+. We find 79 +/- 27 Xi_c0 and 125 +/- 28 Xi_c+ candidates from B decays, leading to product branching fractions of BR(Bbar -> Xi_c0 X)BR(Xi_c0 -> Xi- pi+) = (0.144 +/- 0.048 +/- 0.021) x 10~-3 and BR(Bbar -> Xi_c+ X)BR(Xi_c+ -> Xi- pi+ pi+) = (0.453 +/- 0.096 +0.085-0.065) x 10~-3.

2 data tables
Table 1

Charge conjugated states are included. P(P=4,C=MAX) equals sqrt(Ebeam**2 - m(XI/C)**2). The kinematic limit is : (P(XI/C) / P(P=4,C=MAX)) < 0.5.

Table 2

Charge conjugated states are included. P(P=4,C=MAX) equals sqrt(Ebeam**2 - m(XI/C)**2). The kinematic limit is : (P(XI/C) / P(P=4,C=MAX)) < 0.5.


A measurement of the QCD colour factors and a limit on the light gluino.

The ALEPH collaboration Barate, R. ; Buskulic, D. ; Decamp, D. ; et al.
Z.Phys.C 76 (1997) 1-14, 1997.
Inspire Record 440051 DOI 10.17182/hepdata.34162

Using data collected from 1992 to 1995 with the ALEPH detector at LEP, a measurement of the colour factor ratios CA/CF and TF /CF and the strong coupling constant αs = CFαs(MZ)/(2π) has been performed by fitting theoretical predictions simultaneously to the measured differential two-jet rate and angular distributions in four-jet events. The result is found to be in excellent agreement with QCD, {fx4-1} Fixing CA/CF and TF/CF to the QCD values permits a determination of αs(MZ) and ηf, the number of active flavours. With this measurement the existence of a gluino with mass below 6.3 GeV/c2 is excluded at 95% confidence level.

3 data tables
Table 1

Fit A: using all kinematical distributions. NC, CF, and TF are the color factors for SU(3) group, NF is the number of the active flavors.

Table 2

Fit B: using all kinematical distributions, but QCD magnitudes for color factors are used: FA(DEF=NC/CF)) = 2.25 and TF/CF = 0.375. NC, CF, and TF are the color factors for SU(3) group, NF is the number of the active flavors.

Table 3

Fit C: the QCD magnitudes for color factors and NF = 5 are used.


Study of gluon versus quark fragmentation in Upsilon --> g g gamma and e+ e- --> q anti-q gamma events at s**(1/2) = 10-GeV.

The CLEO collaboration Alam, M.S. ; Athar, S.B. ; Ling, Z. ; et al.
Phys.Rev.D 56 (1997) 17-22, 1997.
Inspire Record 439530 DOI 10.17182/hepdata.47233

Using data collected with the CLEO II detector at the Cornell Electron Storage Ring, we determine the ratio R(chrg) for the mean charged multiplicity observed in Upsilon(1S)->gggamma events, to the mean charged multiplicity observed in e+e- -> qqbar gamma events. We find R(chrg)=1.04+/-0.02+/-0.05 for jet-jet masses less than 7 GeV.

1 data table
Table 1

No description provided.


rivet Analysis
Lambda Antilambda production in two-photon interactions at CLEO.

The CLEO collaboration Anderson, S. ; Kubota, Y. ; Lattery, M. ; et al.
Phys.Rev.D 56 (1997) R2485-R2489, 1997.
Inspire Record 439745 DOI 10.17182/hepdata.47140

Using the CLEO detector at the Cornell $e~+e~-$ storage ring, CESR, we study the two-photon production of $\Lambda \overline{\Lambda}$, making the first observation of $\gamma \gamma \to \Lambda \overline{\Lambda}$. We present the cross-section for $ \gamma \gamma \to \Lambda \overline{\Lambda}$ as a function of the $\gamma \gamma$ center of mass energy and compare it to that predicted by the quark-diquark model.

3 data tables
Table 1

No description provided.

Table 2

No description provided.

Table 3

No description provided.


rivet Analysis
Studies of quantum chromodynamics with the ALEPH detector

The ALEPH collaboration Barate, R. ; Buskulic, D. ; Decamp, D. ; et al.
Phys.Rept. 294 (1998) 1-165, 1998.
Inspire Record 428072 DOI 10.17182/hepdata.47582

Previously published and as yet unpublished QCD results obtained with the ALEPH detector at LEP1 are presented. The unprecedented statistics allows detailed studies of both perturbative and non-perturbative aspects of strong interactions to be carried out using hadronic Z and tau decays. The studies presented include precise determinations of the strong coupling constant, tests of its flavour independence, tests of the SU(3) gauge structure of QCD, study of coherence effects, and measurements of single-particle inclusive distributions and two-particle correlations for many identified baryons and mesons.

44 data tables
Table 1

Charged particle sphericity distribution.

Table 2

Charged particle aplanarity distribution.

Table 3

Charged particle Thrust distribution.

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