Barker, A.R.
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rivet Analysis
Multi - Hadronic Events at E(c.m.) = 29-GeV and Predictions of QCD Models from E(c.m.) = 29-GeV to E(c.m.) = 93-GeV

Petersen, A. ; Abrams, G.S. ; Adolphsen, Chris ; et al.
Phys.Rev.D 37 (1988) 1, 1988.
Inspire Record 246184 DOI 10.17182/hepdata.4114

Multihadronic e+e− annihilation events at a center-of-mass energy of 29 GeV have been studied with both the original (PEP 5) Mark II and the upgraded Mark II detectors. Detector-corrected distributions from global shape analyses such as aplanarity, Q2-Q1, sphericity, thrust, minor value, oblateness, and jet masses, and inclusive charged-particle distributions including x, rapidity, p⊥, and particle flow are presented. These distributions are compared with predictions from various multihadron event models which use leading-logarithmic shower evolution or QCD matrix elements at the parton level and string or cluster fragmentation for hadronization. The new generation of parton-shower models gives, on the average, a better description of the data than the previous parton-shower models. The energy behavior of these models is compared to existing e+e− data. The predictions of the models at a center-of-mass energy of 93 GeV, roughly the expected mass of the Z0, are also presented.

74 data tables
Table 1

Aplanarity distribution.

Table 2

QX Distribution(QX=SQRT(3)*(Q3-Q2)).

Table 3

The (Q2-Q1) distribution.

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rivet Analysis
EXCLUSIVE PRODUCTION OF PROTON - ANTI-PROTON PAIRS IN TWO PHOTON COLLISIONS AT PEP

The TPC/Two Gamma collaboration Aihara, H. ; Alston-Garnjost, M. ; Avery, R.E. ; et al.
Phys.Rev.D 36 (1987) 3506, 1987.
Inspire Record 246557 DOI 10.17182/hepdata.23356

We report cross sections for the process γγ→pp¯ at center-of-mass energies W from 2.0 to 2.8 GeV. These results have been extracted from measurements of e+e−→e+e−pp¯ at an overall center-of-mass energy of 29 GeV, using the TPC/Two-Gamma facility at the SLAC storage ring PEP. Cross sections for the untagged mode [both photons nearly real] are shown to lie well above QCD predictions. Results are also presented for the single-tagged mode [one photon in the range 0.16<Q2<1.6 (GeV/c)2].

3 data tables
Table 1

Data read from graph in preprint. Statistical errors only.

Table 2

Data read from graph. Statistical errors only.

Table 3

Data read from graph. Statistical errors only.


rivet Analysis
Observation of $\Omega^-$ Production in $e^+ e^-$ Annihilation at 29-{GeV}

Klein, S. ; Himel, T. ; Abrams, G.S. ; et al.
Phys.Rev.Lett. 59 (1987) 2412, 1987.
Inspire Record 247900 DOI 10.17182/hepdata.20175

Inclusive Ω− production in e+e− annihilation at 29 GeV has been measured with the Mark II detector. From an integrated luminosity of 207 pb−1, we determine a production rate of 0.014±0.006±0.004 Ω−, Ω¯+ per hadronic event. This is roughly 35 times the Lund-model prediction of 0.0004 Ω−, Ω¯+ per hadronic event, but comparable to the Webber-model prediction of 0.006 Ω−, Ω¯+ per hadronic event. The large rate of Ω− production, compared with production rates for other baryons, and with theoretical predictions based on diquark models, indicates that spin suppression does not hold for Ω− production.

2 data tables
Table 1

Radiatively corrected inclusive cross section.

Table 2

Extrapolation to full momentum range.


DETERMINATION OF THE TOPOLOGICAL CROSS-SECTIONS OF INELASTIC anti-d d INTERACTIONS AT 12-GeV/c

The Dubna-Bucharest-Yerevan-Kosice-Moscow-Prague-Sofiya collaboration Batyunya, B.V. ; Boguslavsky, I.V. ; Bruncko, D. ; et al.
JINR-P1-87-523, 1987.
Inspire Record 251575 DOI 10.17182/hepdata.38882

None

3 data tables
Table 1

No description provided.

Table 2

No description provided.

Table 3

No description provided.


rivet Analysis
Determination of $\alpha^- s$ From Energy-energy Correlations in $e^+ e^-$ Annihilation at 29-{GeV}

Wood, D.R. ; Petersen, A. ; Abrams, G.S. ; et al.
Phys.Rev.D 37 (1988) 3091, 1988.
Inspire Record 250899 DOI 10.17182/hepdata.23323

We have studied the energy-energy correlation in e+e− annihilation into hadrons at √s =29 GeV using the Mark II detector at the SLAC storage ring PEP. We find to O(αs2) that αs=0.158±0.003±0.008 if hadronization is described by string fragmentation. Independent fragmentation schemes give αs=0.10–0.14, and give poor agreement with the data. A leading-log shower fragmentation model is found to describe the data well.

6 data tables
Table 1

Correlation data from the original PEP-5 detector.

Table 2

Correlation Asymmetry data from the original PEP-5 detector.

Table 3

Correlation data from the upgraded detector.

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THE STUDY OF THE NEUTRON STRANGE PARTICLES AND gamma QUANTUM PRODUCTION IN anti-d d INTERACTIONS AT 12-GeV/c

Batyunya, B.V. ; Boguslavsky, I.V. ; Bruncko, D. ; et al.
JINR-P1-87-802, 1987.
Inspire Record 253863 DOI 10.17182/hepdata.9417

None

9 data tables
Table 1

No description provided.

Table 2

No description provided.

Table 3

No description provided.

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THE STUDY OF anti-n n INTERACTIONS AT 6.1-GeV/c

The Dubna-Bucharest-Yerevan-Kosice-Moscow-Prague-Sofiya collaboration Batyunya, B.V. ; Boguslavsky, I.V. ; Bruncko, D. ; et al.
Sov.J.Nucl.Phys. 48 (1988) 475, 1988.
Inspire Record 253864 DOI 10.17182/hepdata.9420

None

21 data tables
Table 1

No description provided.

Table 2

No description provided.

Table 3

No description provided.

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THE STUDY OF INCLUSIVE CHARACTERISTICS OF anti-d d INTERACTIONS AT 12-GeV/c

Batyunya, B.V. ; Boguslavsky, I.V. ; Bruncko, D. ; et al.
JINR-P1-87-849, 1987.
Inspire Record 253758 DOI 10.17182/hepdata.9416

None

8 data tables
Table 1

THE BETTER FIT FOR PI- AND BARIONBAR IS THE SUM OF TWO EXPONENT: A*EXP(-B1*PT**2)+D*EXP(-B2*PT**2).FOR PI- B1=30+-4 AND B2=6.3+-.3 .FOR BARIONBAR B1=46+-18 AND B2=3.9+-.5.

Table 2

No description provided.

Table 3

No description provided.

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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
Table 1

UNTAGGED DATA.

Table 2

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.

Table 3

UNTAGGED DATA.

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LAMBDA (1520) PRODUCTION IN NEUTRON - NUCLEON INTERACTIONS AT approximately 40-GeV NEUTRON ENERGY

Krastev, V.R. ; Aleev, A.N. ; Arefev, V.A. ; et al.
JINR-P1-88-31, 1988.
Inspire Record 261871 DOI 10.17182/hepdata.9450

None

6 data tables
Table 1

AVERAGE OVER ALL TARGETS.

Table 2

No description provided.

Table 3

No description provided.

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