Fabbri, F.
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Search for the Production of a New Quark Flavor at the Highest {PETRA} Energies

Barber, D.P. ; Becker, U. ; Benda, H. ; et al.
Phys.Rev.Lett. 44 (1980) 1722, 1980.
Inspire Record 152616 DOI 10.17182/hepdata.20702

This paper reports the results of a study of hadron production in e+e− collisions at c.m. system energies of 33, 35, and 35.8 GeV. Production of a new quark flavor has been sought. The measured values of the total cross section, the thrust distributions, and the study of inclusive muon production show no evidence for the production of a new charge-23e quark near threshold. In addition, during an energy scan in the region 29.9<~s<~31.6 GeV, no hadron resonance indicating the existence of a bound state composed of charge-23e quarks has been found.

3 data tables
Table 1

No description provided.

Table 2

ENERGY SCAN IN 20 MEV STEPS.

Table 3

THRUST DISTRIBUTION (1/N)*DN/DTHRUST AT 29.9 TO 31.6 AND 35 GEV. THESE DATA ARE RATHER DETECTOR DEPENDENT.


Electroproduction of $\rho^0$ Mesons

Cohen, I. ; Erickson, R. ; Messing, F. ; et al.
Phys.Rev.D 25 (1982) 634, 1982.
Inspire Record 152921 DOI 10.17182/hepdata.47139

Cross sections for ρ0 electroproduction measured in a streamer-chamber experiment are separated into elastic (ep→epρ0) and inelastic production channels. For the elastic channel, the total cross section and t dependence are presented. For the inelastic channel (1σ)dσdz, (1σ)dσdpT2, and a density matrix element are shown and compared to quark-parton-model predictions. The ratio of ρ0 to direct π0 production is found to be 2.0±0.5±0.3, where the first error is statistical, and the second error is systematic.

8 data tables
Table 1

No description provided.

Table 2

No description provided.

Table 3

No description provided.

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rivet Analysis
Total Cross-section for Hadron Production by Electron - Positron Annihilation at Adone

Ambrosio, M. ; Paternoster, G. ; Tortora, L. ; et al.
Phys.Lett.B 91 (1980) 155-160, 1980.
Inspire Record 152630 DOI 10.17182/hepdata.27239

The total cross section for electron-positron annihilation into three or more hadrons has been measured for centre of mass energies between 1.4 and 2.0 GeV. The data were obtained at ADONE by the BB̄ experiment.

1 data table
Table 1

NOTE THAT THIS MEASUREMENT OF R EXCLUDES TWO-BODY FINAL STATE EVENTS. RADIATIVE CORRECTIONS WERE APPLIED.


Observation of Three Upsilon States

The CLEO collaboration Andrews, D. ; Berkelman, Karl ; Billing, M. ; et al.
Phys.Rev.Lett. 44 (1980) 1108, 1980.
Inspire Record 152393 DOI 10.17182/hepdata.20733

Three narrow resonances have been observed in e+e− annihilation into hadrons at total energies between 9.4 and 10.4 GeV. Measurements of mass spacing and ratios of lepton pair widths support the interpretation of these "ϒ" states as the lowest triplet-S levels of the bb¯ quark-antiquark system.

1 data table
Table 1

No description provided.


Inclusive Production of $\rho^0$ and $\phi$ in $K^+ p$ Interactions at 32-{GeV}/c

The Soviet-CERN collaboration Vorobjev, A.P. ; Gerdyukov, L.N. ; Knyazev, V.V. ; et al.
Nucl.Phys.B 176 (1980) 303, 1980.
Inspire Record 153559 DOI 10.17182/hepdata.48999

Inclusive ϱ 0 and φ production is investigated in K + p interactions at 32 GeV/ c . Total and semi-inclusive ϱ 0 and φ cross sections, longitudinal and transverse momentum distributions, including 〈 P T versus x dependence are presented. No evidence for a sea-gull effect is observed. Comparison with quark models strongly suggests the possibility that a large fraction of the ϱ 0 and vector mesons are produced as fragmentation products of the incident particles. Study of uncorrelated π + π − pairs in the ϱ 0 mass range provides possible indirect evidence for the existence of diquarks in the proton.

39 data tables
Table 1

No description provided.

Table 2

No description provided.

Table 3

No description provided.

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Inclusive $K^*$+ (892) and $K^*$ (892) Production in $K^+ p$ Interactions at 32-{GeV}/c

The French-Soviet & CERN-Soviet collaborations Azhinenko, I.V. ; Bryzgalov, V.V. ; Gerdyukov, L.N. ; et al.
Z.Phys.C 5 (1980) 177, 1980.
Inspire Record 153557 DOI 10.17182/hepdata.71085

Total and semi-inclusive cross sections, longitudinal and transverse momentum distributions and spin density matrix elements of theK*+(892) andK*0(892) produced in the inclusive reactionsK+p→K*+(892)+X andK+p→K*0(892)+X at 32 GeV/c are studied in detail. The inclusive spectra of theK*(892) and their decay products are compared with pion and neutral kaon production. TheK*+(892) andK*+(892) are dominantly produced by kaon fragmentation processes. The dependence of average transverse momentum <pT> vs.x for resonances has been investigated for the first time.

55 data tables
Table 1

No description provided.

Table 2

No description provided.

Table 3

No description provided.

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INCLUSIVE K0, LAMBDA0, K*+- (890), AND SIGMA*+- (1385) PRODUCTION IN P P COLLISIONS AT 300-GEV/C

Lopinto, F. ; Brody, A. ; Engelmann, R. ; et al.
Phys.Rev.D 22 (1980) 573-581, 1980.
Inspire Record 158990 DOI 10.17182/hepdata.24150

Inclusive K0K¯0, Λ0, and Λ¯0 cross sections have been determined using a 292-event/mb exposure of the hydrogen-filled 15-foot bubble chamber at Fermilab. From the invariant-mass distributions of V0π± pairs we find that σ(K*±(890))=4.4±1.4 mb, σ(Σ*±(1385))=0.54±0.40 mb, and σ(Σ¯*±(1385))=0.45±0.34 mb. It is estimated that 0.32 ± 0.11 of K0K¯0's, 0.21 ± 0.16 of Λ's, and 0.96 ± 0.75 of Λ¯'s originate from decays of K*(890) and Σ*(1385), respectively.

3 data tables
Table 1

No description provided.

Table 2

No description provided.

Table 3

No description provided.


Test of {QED} in the Reactions $e^+ e^- \to e^+ e^-$ and $e^+ e^- \to \mu^+ \mu^-$ at {CMS} Energies From 9.4-{GeV} to 31.6-{GeV}

The PLUTO collaboration Berger, Christoph ; Genzel, H. ; Grigull, R. ; et al.
Z.Phys.C 4 (1980) 269, 1980.
Inspire Record 152289 DOI 10.17182/hepdata.15600

None

2 data tables
Table 1

No description provided.

Table 2

No description provided.


CROSS-SECTIONS FOR PI- + P ---> N + (K) PI0 (K = 1 TO 5) AND PI- + P ---> N + ETA0 (ETA0 ---> 2 GAMMA) FOR INCIDENT PION MOMENTA BETWEEN 1.3-GEV/C AND 3.8-GEV/C

Crouch, H.R. ; Hargraves, R. ; Lanou, R.E. ; et al.
Phys.Rev.D 21 (1980) 3023-3058, 1980.
Inspire Record 158169 DOI 10.17182/hepdata.4334

This paper presents the results of a study of the dominant neutral final states from π−p interactions. The data were obtained in an experiment performed at the Brookhaven National Laboratory Alternating Gradient Synchrotron, using a set of steel-plate optical spark chambers surrounding a liquid-hydrogen target. We present differential and total cross sections for the reactions (1) π−p→n+π0 and (2) π−p→n+η0(η0→2γ) and total cross sections for the reactions (3) π−p→n+kπ0 (k=2, 3, 4, and 5) and (4) π−p→all neutrals for eighteen values of beam momentum in the interval 1.3 to 4.0 GeV/c. The angular distributions for (1) and (2) have been analyzed in terms of expansions in Legendre polynomials, the coefficients for which are also given.

41 data tables
Table 1

No description provided.

Table 2

SIG = 4*PI*LEG(L=0).

Table 3

FORWARD DIFFERENTIAL CROSS SECTION CALCULATED FROM LEGENDRE POLYNOMIAL COEFFICIENTS AND ERROR MATRICES.

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rivet Analysis
Search for Narrow Resonances in $e^+ e^-$ Annihilation at {PETRA}

The PLUTO collaboration Berger, Christoph ; Genzel, H. ; Grigull, R. ; et al.
Phys.Lett.B 91 (1980) 148-151, 1980.
Inspire Record 152291 DOI 10.17182/hepdata.27236

We have performed a search for narrow resonances in the center of mass energy range from 29.90 to 31.46 GeV using the e + e − storage ring PETRA at DESY. We present the total cross section for hadron production and an upper limit for resonance production, indicating that no bound state of charge- 2 3 quarks exists in this energy range.

2 data tables
Table 1

AVERAGE VALUE OF R OVER THE SCAN REGION.

Table 2

THESE MEASUREMENTS COMBINED WITH PREVIOUS DATA AT 30.0 AND 31.6 GEV REPORTED IN CH. BERGER ET AL., PL 86B, 413 (1979).