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

Sphericity distribution.

Sphericity distribution.

Aplanarity distribution.

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Production of Four Prong Final States in Photon-photon Collisions

The TPC/Two Gamma collaboration Aihara, H. ; Alston-Garnjost, M. ; Avery, R.E. ; et al.
Phys.Rev.D 37 (1988) 28, 1988.
Inspire Record 261630 DOI 10.17182/hepdata.3824

Results are presented on the exclusive production of four-prong final states in photon-photon collisions from the TPC/Two-Gamma detector at the SLAC e+e− storage ring PEP. Measurement of dE/dx and momentum in the time-projection chamber (TPC) provides identification of the final states 2π+2π−, K+K−π+π−, and 2K+2K−. For two quasireal incident photons, both the 2π+2π− and K+K−π+π− cross sections show a steep rise from threshold to a peak value, followed by a decrease at higher mass. Cross sections for the production of the final states ρ0ρ0, ρ0π+π−, and φπ+π− are presented, together with upper limits for φρ0, φφ, and K*0K¯ *0. The ρ0ρ0 contribution dominates the four-pion cross section at low masses, but falls to nearly zero above 2 GeV. Such behavior is inconsistent with expectations from vector dominance but can be accommodated by four-quark resonance models or by t-channel factorization. Angular distributions for the part of the data dominated by ρ0ρ0 final states are consistent with the production of JP=2+ or 0+ resonances but also with isotropic (nonresonant) production. When one of the virtual photons has mass (mγ2=-Q2≠0), the four-pion cross section is still dominated by ρ0ρ0 at low final-state masses Wγγ and by 2π+2π− at higher mass. Further, the dependence of the cross section on Q2 becomes increasingly flat as Wγγ increases.

12 data tables

UNTAGGED DATA.

TAGGED DATA, RESULTS OBTAINED USING TRANSVERSE-TRANSVERSE LUMINOSITY ONLY. DATA FOR Q2=0 ARE FROM UNTAGGED SAMPLE, ERRORS DUE TO RELATIVE NORMALISATION OF THESE SAMPLES IS INCLUDED INTO ERRORS QUOTED.

UNTAGGED DATA.

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Fast neutron production (p(n) >= 1-GeV/c) in p p and p C-12 interactions at p = 4.2-GeV/c and 10-GeV/c.

Bekmirzaev, R.N. ; Grishin, V.G. ; Grishina, O.V. ; et al.
Sov.J.Nucl.Phys. 49 (1989) 637-639, 1989.
Inspire Record 253442 DOI 10.17182/hepdata.9459

None

5 data tables

No description provided.

No description provided.

No description provided.

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INCLUSIVE AND MULTIPLE CHARACTERISTICS OF CUMULATIVE PROTONS IN NUCLEUS-NUCLEUS INTERACTIONS AT 4.2-GeV/c PER NUCLEON

Gulkanian, G.R. ; Ravinovich, I.M. ; Cheplakov, A.P. ;
Sov.J.Nucl.Phys. 50 (1989) 259, 1989.
Inspire Record 267866 DOI 10.17182/hepdata.9447

None

11 data tables

No description provided.

No description provided.

No description provided.

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INVESTIGATION OF COMPTON EFFECT ON pi MESON AND CHARGED PION POLARIZABILITY

The SIGMA-AYaKS & Dubna-Serpukhov-Tbilisi collaborations Antipov, Yu.M. ; Batarin, V.A. ; Bezzubov, V.A. ; et al.
JINR-P1-86-710, 1986.
Inspire Record 239905 DOI 10.17182/hepdata.9549

None

4 data tables

No description provided.

No description provided.

No description provided.

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No description provided.

No description provided.

No description provided.

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LAMBDA AND K0(S) PRODUCTION IN INELASTIC AND MULTI - NUCLEON C C INTERACTIONS AT 4.2-GeV/c PER NUCLEON

Armutliisky, D.D. ; Bogdanovich, E. ; Gasparian, A.P. ; et al.
JINR-P1-85-220, 1985.
Inspire Record 216729 DOI 10.17182/hepdata.9643

None

10 data tables

No description provided.

No description provided.

No description provided.

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THE STUDY OF DIFFRACTIVE DISSOCIATION IN THE REACTION anti-p p ---> anti-p p pi+ pi- AT 22.4-GeV/c

The Dubna-Alma Ata-Helsinki-Prague collaboration Batyunya, B.V. ; Boguslavsky, I.V. ; Dashian, N.B. ; et al.
JINR-E1-82-415, 1982.
Inspire Record 179201 DOI 10.17182/hepdata.9875

None

5 data tables

No description provided.

No description provided.

No description provided.

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DIFFERENTIAL CROSS-SECTION OF THE pi+ p ---> K+ SIGMA+ (1385) REACTION AT 12-GeV/c

The Dubna-Serpukhov-Baku-Bratislava-Kosice-Minsk-Samarkand-Tbilisi collaboration Bitsadze, G.S. ; Budagov, Yu.A. ; Vinogradov, V.B. ; et al.
JINR-P1-84-658, 1984.
Inspire Record 207769 DOI 10.17182/hepdata.9877

None

7 data tables

Axis error includes +- 0.0/0.0 contribution (?////NOT GIVEN).

Axis error includes +- 0.0/0.0 contribution (?////NOT GIVEN).

No description provided.

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QUASIELASTIC PRODUCTION OF LAMBDA HYPERON IN ANTI-NEUTRINO INTERACTIONS AT HIGH-ENERGIES

Ammosov, V.V. ; Asratian, A.E. ; Gapienko, V.A. ; et al.
JETP Lett. 43 (1986) 716-719, 1986.
Inspire Record 240170 DOI 10.17182/hepdata.2210

None

2 data tables

No description provided.

No description provided.