Chen, Charlie
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rivet Analysis
Search for Top Quark and a Test of Models Without Top Quark at the Highest {PETRA} Energies

Adeva, B. ; Barber, D.P. ; Becker, U. ; et al.
Phys.Rev.Lett. 50 (1983) 799, 1983.
Inspire Record 182337 DOI 10.17182/hepdata.20549

With a PETRA energy scan in ≤30-MeV steps, the continuum production of open top quark up to 38.54 GeV is excluded. Over regions of energy scan from 29.90 to 38.63 GeV limits are set on the product of hadronic branching ratio and electronic width BhΓee for toponium to be less than 2.0 keV at the 95% confidence level. By a search for flavor-changing neutral currents in b decay, models without a top quark are excluded.

4 data tables
Table 1

MEASUREMENT OF R IN ENERGY SCAN FROM SQRT(S) = 29.9 TO 3.146 AND 33.0 TO 36.72.

Table 2

MEASUREMENT OF R IN THE RANGE SQRT(S) 37 TO 38.63 GEV.

Table 3

THRUST DISTRIBUTION FOR EVENTS IN THE RANGE SQRT(S) 37.94 TO 38.63 AND 38.54 TO 38.63.

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Coupling Strengths of Weak Neutral Currents From Leptonic Final States at 22-{GeV} and 34-{GeV}

The CELLO collaboration Behrend, H.J. ; Chen, C. ; Fenner, H. ; et al.
Z.Phys.C 16 (1983) 301, 1983.
Inspire Record 180756 DOI 10.17182/hepdata.16385

Differential cross sections fore+e−→e+e−, τ+, τ- measured with the CELLO detector at\(\left\langle {\sqrt s } \right\rangle= 34.2GeV\) have been analyzed for electroweak contributions. Vector and axial vector coupling constants were obtained in a simultaneous fit to the three differential cross sections assuming a universal weak interaction for the charged leptons. The results,v2=−0.12±0.33 anda2=1.22±0.47, are in good agreement with predictions from the standardSU(2)×U(1) model for\(\sin ^2 \theta _w= 0.228\). Combining this result with neutrino-electron scattering data gives a unique axial vector dominated solution for the leptonic weak couplings. Assuming the validity of the standard model, a value of\(\sin ^2 \theta _w= 0.21_{ - 0.09}^{ + 0.14}\) is obtained for the electroweak mixing angle. Additional vector currents are not observed (C<0.031 is obtained at the 95% C.L.).

2 data tables
Table 1

No description provided.

Table 2

Combined MU and TAU asymmetry. See PL 114B(1982)282 (<a href=http://durpdg.dur.ac.uk/scripts/reacsearch.csh/TESTREAC/red+1234> RED = 1234 </a>) and ZP C14(1982)283 (<a href=http://durpdg.dur.ac.uk/scripts/reacsearch.csh/TESTREAC/red+1245> RED = 1245 </a>) for individual asymmetry measurements.


rivet Analysis
Measurement of R in $e^+ e^-$ Annihilation for $\sqrt{s}$ Between 7.4-{GeV} and 9.4-{GeV}

The LENA collaboration Niczyporuk, B. ; Jakubowski, Z. ; Nowak, G. ; et al.
Z.Phys.C 15 (1982) 299, 1982.
Inspire Record 179431 DOI 10.17182/hepdata.16412

The rationR=σ(e+e−→hadrons)/σ(e+e−→ µ+ µ−) was measured with the LENA detector at DORIS in a scan between 7.40 and 7.48 GeV and between 8.67 and 9.43 GeV center of mass energies. Corrected for QED radiative effects,R is found to be constant with an average value ofR=3.37 ±0.06stat±0.23syst. No narrow resonances withΓee(Γhad/Γtot)⊗0.30 keV (95% C.L.) and no steps have been observed. Based on this value ofR, revised values for υ(1S) resonance parameters are presented.

3 data tables
Table 1

No description provided.

Table 2

No description provided.

Table 3

NUMERICAL VALUES GIVEN IN APPENDIX IN PREPRINT. STATISTICAL ERRORS ONLY.


The Influence of Fragmentation Models on the Determination of the Strong Coupling Constant in $e^+ e^-$ Annihilation Into Hadrons

The CELLO collaboration Behrend, H.J. ; Chen, C. ; Fenner, H. ; et al.
Nucl.Phys.B 218 (1983) 269-288, 1983.
Inspire Record 179447 DOI 10.17182/hepdata.8172

Hadronic events obtained with the CELLO detector at PETRA were compared with first-order QCD predictions using two different models for the fragmentation of quarks and gluons, the Hoyer model and the Lund model. Both models are in reasonable agreement with the data, although they do not completely reproduce the details of many distributions. Several methods have been applied to determine the strong coupling constant α S . Although within one model the value of α S varies by 20% among the different methods, the values determined using the Lund model are 30% or more larger (depending on the method used) than the values determined with the Hoyer model. Our results using the Hoyer model are in agreement with previous results based on this approach.

3 data tables
Table 1

DATA CORRECTED WITH HOYER MODEL (ALPHA-S=0.15).

Table 2

DATA CORRECTED WITH LUND MODEL (ALPHA-S=0.25).

Table 3

No description provided.


rivet Analysis
Inclusive Charged $D^*$ Production in $e^+ e^-$ Annihilations at $W=10$.4-{GeV}

The CLEO collaboration Bebek, C. ; Hassard, J. ; Hempstead, M. ; et al.
Phys.Rev.Lett. 49 (1982) 610, 1982.
Inspire Record 178490 DOI 10.17182/hepdata.20565

A measurement is presented of inclusive charged D*(2010) production from nonresonant e+e− annihilation in the center-of-mass energy (W) range 10.2 GeV<W<10.6 GeV. Charged D* mesons are identified by the decays D*+→D0π+→K−π+π+ and the charge conjugate mode. It is found that 40 ± 7 ± 13% of the charm quarks from the process e+e−→cc¯ result in D* mesons with z>0.7 (z=2EW, where E is the D* energy).

2 data tables
Table 1

No description provided.

Table 2

No description provided.


Charged Particle Multiplicities in $B$ Meson Decay

The CLEO collaboration Alam, M.S. ; Csorna, S.E. ; Fridman, A. ; et al.
Phys.Rev.Lett. 49 (1982) 357, 1982.
Inspire Record 178492 DOI 10.17182/hepdata.20573

The charged multiplicity has been measured at the ϒ(4S) and a value of 5.75±0.1±0.2 has been obtained for the mean charged multiplicity in B-meson decay. Combining this result with the measurement of prompt leptons from B decay, the values 4.1±0.35±0.2 and 6.3±0.2±0.2 are found for the semileptonic and nonleptonic charged multiplicities, respectively. If b→c dominance is assumed for the weak decay of the B meson, then the semileptonic multiplicity is consistent with the recoil mass determined from the lepton momentum spectrum.

2 data tables
Table 1

No description provided.

Table 2

No description provided.


rivet Analysis
Analysis of the Energy Weighted Angular Correlations in Hadronic $e^+ e^-$ Annihilations at 22-{GeV} and 34-{GeV}

The CELLO collaboration Behrend, H.J. ; Chen, C. ; Fenner, H. ; et al.
Z.Phys.C 14 (1982) 95, 1982.
Inspire Record 12010 DOI 10.17182/hepdata.16413

Measurements of energy weighted angular correlations in electron positron annihilations at c.m. energies of 22 GeV and 34 GeV are presented.

4 data tables
Table 1

ENERGY-ENERGY CORRELATIONS FOR FINAL STATE PARTICLES.

Table 2

ENERGY-ENERGY CORRELATIONS FOR PRIMORDIAL HADRONS.

Table 3

ASSYMETRY IN ENERGY CORRELATIONS FOR FINAL STATE PARTICLES.

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Measurement of $e^+ e^- \to \tau^+ \tau^-$ at High-energy and Properties of the $\tau$ Lepton

The CELLO collaboration Behrend, H.J. ; Chen, C. ; Fenner, H. ; et al.
Phys.Lett.B 114 (1982) 282-286, 1982.
Inspire Record 177224 DOI 10.17182/hepdata.6667

The e + e − → τ + τ − process has been measured using the CELLO detector at a mean total centre of mass energy of 34.2 GeV using essentially all the decay channels of the τ lepton. The measured cross section yields R τ =1.03±0.05 (stat)±0.07 (syst). Topological branching fraction are given for τ → 1, 3 or 5 charged tracks. The angular distribution shows a clear 1 + cos 2 θ dependance with a forward-backward asymmetry of -0.103 ± 0.052 corresponding to an axial-vector coupling a τ of the τ to the weak neutral current given by a τ =−1.12 ± 0.57.

4 data tables
Table 1

No description provided.

Table 2

No description provided.

Table 3

Forward-backward asymmetry based on 1 + (cos(theta))**2 + bcos(theta) fit for angular distribution.

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Measurement of $e^+ e^- \to \mu^+ \mu^-$ Charge Asymmetry

Adeva, B. ; Barber, D.P. ; Becker, U. ; et al.
Phys.Rev.Lett. 48 (1982) 1701, 1982.
Inspire Record 177308 DOI 10.17182/hepdata.3116

The measurement of the nonelectromagnetic forward-backward charge asymmetry in the reaction e+e−→μ+μ− at s∼34.6 GeV and in the angular region 0<|cosθ|<0.8 is reported. With a systematic error less than 1%, we observe an asymmetry of (-8.1±2.1)%. This is in agreement with the standard electroweak theory prediction of (-7.6±0.6)%. The weak-current coupling constants are also reported.

4 data tables
Table 1

SEE PRL 55, 665 FOR DISTRIBUTIONS AT 34.6 GEV AND ABOVE.

Table 2

SEE PRL 55, 665 FOR CROSS SECTION VALUES AND FORWARD BACKWARD ASYMMETRY.

Table 3

No description provided.

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Measurement of Inclusive $\gamma$ and $\pi^0$ Spectra and a Comparison of the Neutral and Charged Components in Hadronic Events in $e^+ e^-$ Annihilation at 34-{GeV}

The CELLO collaboration Behrend, H.J. ; Chen, C. ; Fenner, H. ; et al.
Z.Phys.C 14 (1982) 189, 1982.
Inspire Record 177212 DOI 10.17182/hepdata.16411

The photonic part of multihadronice+e− annihilation events has been analyzed at a c.m. energy of 34 GeV. The photonic energy fraction per event is determined to befγ=0.251±0.003 (stat.) ±0.04 (syste.). The neutral and charged components of the events are analyzed separately revealing close similarity in thrust axis directions and momentum distributions in agreement with the hypothesis that most photons result from π0 decay. π0's are reconstructed separately and used to determine the inclusive cross section. Comparing these cross sections with lower energy data from SPEAR we find some indication for scaling violation.

2 data tables
Table 1

No description provided.

Table 2

No description provided.