Allison, John
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Observation of Inclusive $\eta$ Production in $e^+ e^-$ Annihilation at {CM} Energies of 34-{GeV}

The JADE collaboration Bartel, W. ; Becker, L. ; Bowdery, C. ; et al.
Phys.Lett.B 130 (1983) 454-458, 1983.
Inspire Record 191416 DOI 10.17182/hepdata.30634

The inclusive production of η mesons at CM energies around 34 GeV has been studied for e + e − annihilation into hadrons. The average number of η-mesons per event is found to be 0.72 ± 0.10 (stat.) ± 0.18 (syst.). The abundance of η's is studied as a function of event shape parameters and it is compared to the corresponding π 0 rates.

2 data tables
Table 1

No description provided.

Table 2

DATA REQUESTED FROM AUTHORS.


Inclusive Photoproduction of Neutral Strange Particles at 20-{GeV}

The SLAC Hybrid Facility Photon collaboration Abe, K. ; Bacon, T.C. ; Ballam, Joseph ; et al.
Phys.Rev.D 29 (1984) 1877, 1984.
Inspire Record 190724 DOI 10.17182/hepdata.23774

We have studied inclusive production of KS0, Λ, and Λ¯ particles in 20-GeV γp interactions and have found features similar to those observed in both hadronic and leptonic interactions. The production cross sections, charged-particle multiplicities, and average Λ polarization are reported. Inclusive distributions of x and pT are shown and discussed in terms of quark fragmentation models. Production cross sections for K*(890) and Σ*(1385) are also reported.

9 data tables
Table 1

No description provided.

Table 2

No description provided.

Table 3

No description provided.

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rivet Analysis
Charged Particle and Neutral Kaon Production in e+ e- Annihilation at PETRA

The JADE collaboration Bartel, W. ; Becker, L. ; Bawbery, C. ; et al.
Z.Phys.C 20 (1983) 187, 1983.
Inspire Record 190818 DOI 10.17182/hepdata.16288

None

5 data tables
Table 1

MEAN CHARGED MULTIPLICITY.

Table 2

MEAN CHARGED MULTIPLICITY AFTER SUBTRACTING SECONDARIES FROM KS AND LAMBDA DECAY, PLUS LEPTONS FROM HEAVY QUARK WEAK DECAYS ARE FROM DALITZ DECAYS. I.E. NUMBER OF CHARGED HADRONS HAVING LIFETIME > 10**-9 SEC.

Table 3

INVERSE RELATIVE DISPERSION.

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Precise Measurement of Total Cross-Sections for the Process e+ e- ---> Multi-Hadrons in the Center-Of-Mass Energy Range Between 12.0-GeV and 36.4-GeV

The JADE collaboration Bartel, W. ; Becker, L. ; Bowdery, C. ; et al.
Phys.Lett.B 129 (1983) 145-152, 1983.
Inspire Record 191159 DOI 10.17182/hepdata.6639

The total cross section for the process e + e − → hadrons has been measured in the CM energy range between 12.0 and 36.4 GeV using the JADE detector with a typical systematic error of ±3%. The ratio R( σ( ee → hadrons ) σ pt ) is found to be constant over this range with an average value of 3.97 ± 0.05 (statistical and point-to-point systematic error) ± 0.10 (normalization error). The data were compared with the standard electro-weak interaction model including QCD corrections.

2 data tables
Table 1

ERRORS ARE STATISTICAL PLUS POINT TO POINT SYSTEMATICS. THERE IS AN ADDITIONAL 2.4 PCT OVERALL NORMALIZATION ERROR.

Table 2

No description provided.


Measurement of the Processes $e^+ e^- \to e^+ e^-$ and $e^+ e^- \to \gamma \gamma$ at {PETRA}

The JADE collaboration Bartel, W. ; Becker, L. ; Bowdery, C. ; et al.
Z.Phys.C 19 (1983) 197, 1983.
Inspire Record 191231 DOI 10.17182/hepdata.45206

Cross sections for the reactionse+e−→e+e− (Bhabha scattering) ande+e−→γγ are measured for center-of-mass (c.m.) energies\(\sqrt s \) between 12.0 and 34.6 GeV. The results agree with the predictions of Quantum Electrodynamics (QED) and the cut-off parameters are determined. From Bhabha scattering at the highest energy,\(\left\langle {\sqrt s } \right\rangle= 34.6 GeV\), the 1 δ limits 0.12<sin2 ϑw<0.38 are obtained for the weak mixing angle. The higher order (α3) QED processese+e−→e+e−γ ande+e−→γγγ are also studied and are found to agree with the α3 QED predictions. A search for excited electrons is carried out by investigating the (e±γ) invariant mass distribution in the reactione+e−→e+e−γ.

3 data tables
Table 1

Total cross sections.

Table 2

Angular distribution.

Table 3

Angular distribution.


CHARM PHOTOPRODUCTION CROSS-SECTION AT 20-GeV

Abe, K. ; Bacon, T.C. ; Ballam, Joseph ; et al.
Phys.Rev.Lett. 51 (1983) 156, 1983.
Inspire Record 189662 DOI 10.17182/hepdata.20508

Forty-seven charm events have been observed in an exposure of the SLAC Hybrid Facility bubble chamber to a 20-GeV backward-scattered laser beam. Thirty-seven events survive all the necessary cuts imposed. Based on this number the total charm cross section is calculated to be 63−28+33 nb.

1 data table
Table 1

No description provided.


STRANGE PARTICLE PRODUCTION IN ANTI-P P ANNIHILATIONS AT 8.8-GEV/C

Hill, J.C. ; Ansorge, R.E. ; Carter, J.R. ; et al.
Nucl.Phys.B 227 (1983) 387, 1983.
Inspire Record 196402 DOI 10.17182/hepdata.33929

Results are presented from an experiment at the SLAC 40″ hybrid facility (SHF) using an 8.8 GeV/ c antiproton beam. Using external detectors and an on-line trigger, a sample of events enriched in p p annihilations was obtained. pp interactions taken under the same conditions enabled the annihilations to be identified. Cross sections and distributions for the inclusive production of K s 0 and K ∗± (890), and cross sections for exclusive channels with a pair of strange particles are presented.

3 data tables
Table 1

No description provided.

Table 2

No description provided.

Table 3

No description provided.


EXISTENCE OF XI RESONANCES ABOVE 2-GEV

Jenkins, Charles M. ; Albright, John R. ; Diamond, R.N. ; et al.
Phys.Rev.Lett. 51 (1983) 951-954, 1983.
Inspire Record 195471 DOI 10.17182/hepdata.20475

Ξ*− production was studied in the reaction K−+p→K+slow+X− at 5 GeV/c. The slow K+ was electronically detected, while the X− was observed as a missing mass, thus allowing for observation of all Ξ* independent of decay mode. The observed Ξ states were Ξ(1320), Ξ(1530), Ξ(1820), Ξ(2030), Ξ(2250), Ξ(2370), and Ξ(2500). These data establish and confirm the existence of Ξ(2250) and indicate a peculiar production-cross-section behavior for the Ξ*(2370).

1 data table
Table 1

UPPER LIMITS ARE 95 PCT CL.


DIFFERENCES BETWEEN ANTI-P P AND P P INTERACTIONS AT 8.8-GeV/c AND THEIR RELATIONSHIP TO ANTI-P P ANNIHILATIONS

Booth, C.n. ; Ansorge, R.e. ; Carter, J.r. ; et al.
Phys.Rev.D 27 (1983) 2018, 1983.
Inspire Record 194364 DOI 10.17182/hepdata.23838

We report on an experiment in which the SLAC 40-in. hybrid facility was exposed to an 8.8-GeV/c antiproton beam. Using external detectors we have identified a large fraction of nonannihilation events and thus obtained a clean sample of annihilation data. Using proton interactions taken in the same detector at the same energy we have made a detailed study of (p¯p−pp) differences and explored their relationship to p¯p annihilations.

27 data tables
Table 1

No description provided.

Table 2

No description provided.

Table 3

No description provided.

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Charm $D$ Meson Production in 360-{GeV} $\pi^- p$ Interactions: Evidence for Leading Quarks

The LEBC-EHS collaboration Aguilar-Benitez, M. ; Allison, W.W.M. ; Bagnaia, P. ; et al.
Phys.Lett.B 123 (1983) 98-102, 1983.
Inspire Record 182456 DOI 10.17182/hepdata.30715

Charm D-meson production in 360 GeV π − p interactions has been studied using the high-resolution hydrogen bubble chamber LEBC and the European Hybrid Spectrometer. The data show evidence for leading quark effects both in the number of D-meson types and in the Feynman x distributions. The production cross section is of the form d 2 δ d x d p T 2 ∞(1-x) n exp (-ap T 2 ) with n = 2.8±0.8 and a = 1.1±0.3 (GeV/ c ) −2 . The x distribution is, however, compatible with the presence of both central ( n = 6) and leading (n = 1) D / D production. The fraction of D-messons in the leading component is estimated to be ≈30%. The rapidity gap between members of reconstructed charm pairs is small compared to the available rapidity range. The inclusive cross section for single D-messons in the forward direction is: δ(D/ D )=(40 8 +15 )μ b ( for x>0) .

1 data table
Table 1

No description provided.