Smith, E.S.
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Inclusive neutral vector meson production in hadronic Z0 decays

The OPAL collaboration Acton, P.D. ; Alexander, G. ; Allison, John ; et al.
Z.Phys.C 56 (1992) 521-536, 1992.
Inspire Record 336772 DOI 10.17182/hepdata.14530

Results are reported of a study of neutral vector meson production in multihadronicZ0 decays in the OPAL experiment at LEP. Pions and kaons have been identified by specific ionisation energy loss andK±π∓ andK+K− mass spectra have been fitted, in bins of the scaled momentum variablexp, to combinations of resonance signals and non-resonant backgrounds. Rates are given forK*(892)° and ø(1020), and production cross sections are compared to the predictions of Monte Carlo models. Overall multiplicities have been determined as 0.76±0.07±0.06K*(892)° and 0.086±0.015±0.010 ø(1020) per hadronicZ0 decay (the quoted errors are respectively statistical and systematic). Momentum dependent distortions of the ππ mass spectra, possibly associated indirectly with Bose-Einstein effects, have prevented reliable measurement of the ρ(770)° cross section in this study.

4 data tables
Table 1

No description provided.

Table 2

No description provided.

Table 3

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The Dijet angular distribution in p anti-p collisions at s**(1/2) = 1.8-TeV

The CDF collaboration Abe, F. ; Amidei, Dante E. ; Anway, Carol E. ; et al.
Phys.Rev.Lett. 69 (1992) 2896-2900, 1992.
Inspire Record 336778 DOI 10.17182/hepdata.19809

The dijet angular distribution is measured in the Collider Detector at Fermilab. This measurement covers higher mass ranges and larger scattering angles than previously possible. Good agreement is observed between the data and both leading-order [O(αs2)] and next-to-leading order [O(αs3)] QCD calculations. A limit on quark compositeness of Λc>1.0 TeV is obtained.

3 data tables
Table 1

No description provided.

Table 2

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Table 3

No description provided.


A Measurement of $\Lambda_{\overline{MS}}$ from $\nu_{\mu}$ - Fe Nonsinglet Structure Functions at the Fermilab Tevatron

Quintas, P.Z. ; Leung, W.C. ; Mishra, S.R. ; et al.
Phys.Rev.Lett. 71 (1993) 1307-1310, 1993.
Inspire Record 336860 DOI 10.17182/hepdata.19733

The CCFR Collaboration presents a measurement of scaling violations of the nonsinglet structure function and a comparison to the predictions of perturbative QCD. The value of ΛQCD, from the nonsinglet evolution with Q2>15 GeV2 and in the modified minimal-subtraction renormalization scheme, is found to be 210±28(stat)±41(syst) MeV.

1 data table
Table 1

The CONST(N=LAMBDA-QCD) is extracted from the measurement of scaling violations of the nonsinglet structure function.


A Measurement of jet shapes in p anti-p collisions at s**(1/2) = 1.8-TeV

The CDF collaboration Abe, F. ; Amidei, Dante E. ; Anway, Carol E. ; et al.
Phys.Rev.Lett. 70 (1993) 713-717, 1993.
Inspire Record 340125 DOI 10.17182/hepdata.19744

We present a measurement of jet shapes in p¯p collisions at √s =1.8 TeV at the Fermilab Tevatron using the Collider Detector at Fermilab (CDF). Qualitative agreement is seen with the predictions of recent next-to-leading [O(αs3)] calculations and with leading logarithm QCD based Monte Carlo simulations. The dependence of the jet shape on transverse energy is studied.

1 data table
Table 1

No description provided.


A Measurement of $J / \psi$ and $\psi^{\prime}$ Production in 300-GeV/c Proton, Antiproton and $\pi^{\pm}$ Nucleon Interactions

The E705 collaboration Antoniazzi, L. ; Arenton, M. ; Cao, Z. ; et al.
Phys.Rev.D 46 (1992) 4828-4835, 1992.
Inspire Record 338055 DOI 10.17182/hepdata.22667

Hadroproduction of the Jψ and ψ′ states has been studied in 300-GeV/c proton, antiproton, and π±Li interactions. Both total and differential cross sections in xF and pT have been measured for the Jψ for the π±, proton, and antiproton interactions. The ratio of ψ′ to Jψ production has been determined for the four types of beam particles.

16 data tables
Table 1

No description provided.

Table 2

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Table 3

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Measurement of the production rates of eta and eta-prime in hadronic Z decays

The ALEPH collaboration Buskulic, D. ; Decamp, D. ; Goy, C. ; et al.
Phys.Lett.B 292 (1992) 210-220, 1992.
Inspire Record 334575 DOI 10.17182/hepdata.29156

The decays η → γγ and η ′ → ηπ + π − have been observed in hadronic decays of the Z produced at LEP. The fragmentation functions of both the η and η ′ have been measured. The measured multiplicities for x > 0.1 are 0.298±0.023±0.021 and 0.068±0.016 for η and η ′ respectively. While the fragmentation function for the η is fairly well described by the JETSET Monte Carlo, it is found that the production rate of the η ′ is a factor of four less than the corresponding prediction.

3 data tables
Table 1

No description provided.

Table 2

Additional 7 pct systematic error.

Table 3

Additional 23 pct systematic error.


Production of $J / \psi$ via $\psi^{\prime}$ and $X$ Decay in 300-GeV/c Proton and $\pi^{\pm}$ Nucleon Interactions

The E705 collaboration Antoniazzi, L. ; Arenton, M. ; Cao, Z. ; et al.
Phys.Rev.Lett. 70 (1993) 383-386, 1993.
Inspire Record 336204 DOI 10.17182/hepdata.19754

The production of the χ1 and χ2 states of charmonium has been observed in 300 GeV/c π±N and pN interactions. The fraction of the total inclusive J/ψ production due to radiative χ decay has been determined to be 0.40±0.04, 0.37±0.03, and 0.30±0.04 for the π+, π−, and proton data, respectively. Total cross sections have been obtained of 131±18±14 and 188±30±21 nb/nucleon in the 300 GeV/c π−N interactions for χ1 and χ2 production. By measuring the contributions to the J/ψ production due to both ψ’ and radiative χ decay, the cross sections for direct J/ψ production have been determined to be 97±14, 102±14, and 89±12 nb/nucleon for π+, π−, and protons, respectively.

8 data tables
Table 1

Fractions of total J/PSI production due to radiative CHI1 and CHI2 decays.

Table 2

Fractions of total J/PSI production due to radiative CHI1 and CHI2 decays.

Table 3

Fractions of total J/PSI production due to radiative CHI1 and CHI2 decays.

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Properties of hadronic Z decays and test of QCD generators

The ALEPH collaboration Buskulic, D. ; Decamp, D. ; Goy, C. ; et al.
Z.Phys.C 55 (1992) 209-234, 1992.
Inspire Record 334577 DOI 10.17182/hepdata.1420

Distributions are presented of event shape variables, jet roduction rates and charged particle momenta obtained from 53 000 hadronicZ decays. They are compared to the predictions of the QCD+hadronization models JETSET, ARIADNE and HERWIG, and are used to optimize several model parameters. The JETSET and ARIADNE coherent parton shower (PS) models with running αs and string fragmentation yield the best description of the data. The HERWIG parton shower model with cluster fragmentation fits the data less well. The data are in better agreement with JETSET PS than with JETSETO(αS2) matrix elements (ME) even when the renormalization scale is optimized.

41 data tables
Table 1

Sphericity distribution.

Table 2

Sphericity distribution.

Table 3

Aplanarity distribution.

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rivet Analysis
Charged particle multiplicity distributions for fixed number of jets in Z0 hadronic decays

The DELPHI collaboration Abreu, P. ; Adam, W. ; Adami, F. ; et al.
Z.Phys.C 56 (1992) 63-76, 1992.
Inspire Record 334948 DOI 10.17182/hepdata.14533

The multiplicity distributions of charged particles in full phase space and in restricted rapidity intervals for events with a fixed number of jets measured by the DELPHI detector are presented. The data are well reproduced by the Lund Parton Shower model and can also be well described by fitted negative binomial distributions. The properties of these distributions in terms of the clan model are discussed. In symmetric 3-jet events the candidate gluon jet is found not to be significantly different in average multiplicity than the mean of the other two jets, thus supporting previous results of the HRS and OPAL experiments. Similar results hold for events generated according to the LUND PS and to the HERWIG models, when the jets are defined by the JADE jet finding algorithm. The method seems to be insensitive for measuring the color charge ratio between gluons and quarks.

3 data tables
Table 1

Corrected charged particle multiplicity for jet resolution parameter YCUT = 0.01.

Table 2

Corrected charged particle multiplicity for jet resolution parameter YCUT = 0.02.

Table 3

Corrected charged particle multiplicity for jet resolution parameter YCUT = 0.04.


Nucleon structure functions from high energy neutrino interactions

Oltman, E. ; Auchincloss, Priscilla S. ; Blair, R.E. ; et al.
Z.Phys.C 53 (1992) 51-71, 1992.
Inspire Record 335706 DOI 10.17182/hepdata.1433

Structure functions obtained from high energy neutrino and antineutrino scattering from an iron target are presented. These were extracted from the combined data of Fermilab experiments E616 and E701; these utilized narrow band beam runs between 1979–1982. The structure functions are used to test the validity of quarkparton model (QPM) predictions and to extract the QCD scale parameter Λ from fits to the Altarelli-Parisi equations.

22 data tables
Table 1

No description provided.

Table 2

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Table 3

No description provided.

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