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rivet Analysis
Determination of alpha-s and sin**2theta(w) from Measurements of the Total Hadronic Cross-Section in e+ e- Annihilation

The CELLO collaboration Behrend, H.J. ; Burger, J. ; Criegee, L. ; et al.

Phys.Lett.B 183 (1987) 400-411, 1987.

Inspire Record 236981 DOI 10.17182/hepdata.30231

We have measured the total normalized cross section R for the process e + e − → hadrons at centre-of-mass energies between 14.0 and 46.8 GeV based on an integrated luminosity of 60.3 pb −1 . The data are well described by the standard SU(3) c ⊗SU(2) L ⊗U(1) model with the production of the five known quarks. No open production of a sixth quark with charge 2/3 or 1/3 occurs below a centre-of-mass energy of 46.6 or 46.3 GeV, respectively. A fitting procedure which takes the correlations between measurements into account was used to determine the electroweak mixing angle sin 2 θ w and the strong coupling constant α s ( S ) in second-order QCD. We applied this procedure to the CELLO data and in addition included the data from other experiments at PETRA and PEP. Both fits give consistent results. The fit to the combined data yields α s (34 2 GeV 2 ) = 0.165±0.030, and sin 2 θ w = 0.236±0.020. Fixing sin 2 θ w at the world average value of 0.23 yields α s (34 2 GeV 2 ) = 0.169±0.025.

2 data tables

Table 1

No description provided.

Table 2

No description provided.

STUDY OF BARYON CORRELATIONS IN e+ e- ANNIHILATION AT 29-GeV

The TPC/Two Gamma collaboration Aihara, H. ; Alston-Garnjost, M. ; Avery, R.E. ; et al.

Phys.Rev.Lett. 57 (1986) 3140, 1986.

Inspire Record 236028 DOI 10.17182/hepdata.20193

We report measurements of two-particle correlations in rapidity space between a p¯ or Λ¯ and an additional p, p¯, Λ, or Λ¯. We find evidence for local conservation of baryon number, and for the first time observe a pronounced anticorrelation between baryons with the same value of baryon number. Such an anticorrelation is expected in fragmentation models where the rapidity order of particles closely reflects their ‘‘color order,’’ as is the case, for example, in recent versions of the Lund string model.

1 data table

Table 1

No description provided.

COMPARISON BETWEEN HADRONIC FINAL STATES PRODUCED IN mu p AND e+ e- INTERACTIONS

The European Muon collaboration Arneodo, M. ; Arvidson, A. ; Aubert, J.J. ; et al.

Z.Phys.C 35 (1987) 417, 1987.

Inspire Record 233424 DOI 10.17182/hepdata.16655

A comparison is made between the properties of the final state hadrons produced in 280 GeV μp interactions and ine+e− annihilation. The Lund model of hadroproduction is used as an aid in understanding the differences observed. The hadron distributions from μp ande+e− interactions are consistent with the quark parton model assumption of environmental independence, provided that the differences in heavy quark production and hard QCD effects in the two processes are taken into account. A comparison with aK+p experiment is also made. Values are also determined for the Lund model parameters σq = 0.410 ± 0.002 ± 0.020 GeV and σ′ = 0.29−0.15 −0.13+0.09+0.10 GeV, controlling the transverse momenta in fragmentation and intrinsic transverse momenta of the struck quark respectively.

23 data tables

Table 1

With respect to the virtual photon axis.

Table 2

With respect to the sphericity axis.

Table 3

With respect to the thrust axis.

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Observation of Charge Asymmetry in Hadron Jets From $e^+ e^-$ Annihilation at $\sqrt{s}=29$-{GeV}

Ash, W. ; Band, H. ; Camporesi, T. ; et al.

Phys.Rev.Lett. 58 (1987) 1080, 1987.

Inspire Record 231267 DOI 10.17182/hepdata.20184

A charge asymmetry has been observed in final-state jets from e+e− annihilation into hadrons at √s =29 GeV. The measured asymmetry is consistent with the prediction of electroweak theory. The product of axial-vector weak coupling constants, averaged over all quark flavors, is determined to be 〈gAegAq〉=-0.34±0.06±0.05.

1 data table

Table 1

Measured differential cross section after efficiency and radiative cross sections. THETA is the polar-angle of the thrust axis defined to be the angle between the direction of the incident positron and the thrust axis taken in the direction of the positron jet. Numerical values requested from the authors. Data are normalised to the total expected QED cross section.

Measurement of Neutrino - Proton and anti-neutrino - Proton Elastic Scattering

Ahrens, L.A. ; Aronson, S.H. ; Connolly, P.L. ; et al.

Phys.Rev.D 35 (1987) 785, 1987.

Inspire Record 18763 DOI 10.17182/hepdata.23350

Measurements of the semileptonic weak-neutral-current reactions νμp→νμp and ν¯μp→ν¯μp are presented. The experiment was performed using a 170-metric-ton high-resolution target detector in the BNL wide-band neutrino beam. High-statistics samples yield the absolute differential cross sections dσ(νμp)/dQ2 and dσ(ν¯μp)/dQ2. A measurement of the axial-vector form factor GA(Q2) is also presented. The results are in good agreement with the standard model SU(2)×U(1). The weak-neutral-current parameter sin2thetaW is determined to be sin2θW=0.220±0.016(stat)−0.031+0.023(syst).

1 data table

Table 1

Errors contain both statistics and systematics, except for additional overall normalisation error given above. Neutrino energy is 0 to 5 GeV with peak at 0.8 Gev.

rivet Analysis
A Study of the Decay $B \to \psi$ X

The CLEO collaboration Alam, M.S. ; Katayama, N. ; Kim, I.J. ; et al.

Phys.Rev.D 34 (1986) 3279, 1986.

Inspire Record 230961 DOI 10.17182/hepdata.23447

We have measured the inclusive branching ratio for B→ψX to be (1.09±0.16±0.21)%, and the exclusive branching ratios for B−→ψK− and B¯ ¯0 *0 to be (0.09±0.05)% and (0.41±0.18)%, respectively. The mass difference between neutral and charged B mesons is 1.1±2.1 MeV, while the difference between the mass of Υ(4S) and twice the mean B-meson mass is 18.5±3.0 MeV. The ψ momentum distribution implies a substantial two-body decay (in agreement with direct measurements), but also some combination of B→ψX with MX>1.5 GeV, and B→ψ’X.

2 data tables

Table 1

No error for cross-section given in text.

Table 2

No description provided.

$\rho^0$ and $\omega$ Production in Deep Inelastic $\mu p$ Interactions at 280-{GeV}/$c$

The European Muon collaboration Arneodo, M. ; Arvidson, A. ; Aubert, J.J. ; et al.

Z.Phys.C 33 (1986) 167, 1986.

Inspire Record 231103 DOI 10.17182/hepdata.15815

Inclusive distributions of ρ0 and ω mesons have been measured in deep inelastic μ-p interactions at 280 GeV/c. A comparison of the ρ0 cross sections with other leptoproduction experiments is presented. The ω results represent the first observation of this inclusive channel in high energy leptoproduction. The ρ0 and ω yields are found to be equal as may be expected from the available density of states in isospin space. This contrasts with spin angular momentum where the vector to pseudoscalar meson ratio is suppressed relative to the available number of spin states.

4 data tables

Table 1

No description provided.

Table 2

No description provided.

Table 3

No description provided.

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Charm Production in Deep Inelastic Muon - Iron Interactions at 200-{GeV}/$c$

The European Muon collaboration Arneodo, M. ; Aubert, J.J. ; Bassompierre, G. ; et al.

Z.Phys.C 35 (1987) 1, 1987.

Inspire Record 230629 DOI 10.17182/hepdata.15765

Dimuon and trimuon events have been studied in deep inelastic muon scattering on an iron target at an incident muon energy of 200 GeV. The events are shown to originate mainly from charm production. Comparison of the measured cross sections with data taken at higher muon energies shows that charm production originates predominantly from transverse virtual photons. Within the framework of the photon gluon fusion model this indicates that the parity of the gluon is odd.

1 data table

Table 1

No description provided.