Blobel, V.
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Topology of Hadronic $e^+ e^-$ Annihilation Events at 22-{GeV} and 34-{GeV} Center-of-mass Energy

The CELLO collaboration Behrend, H.J. ; Chen, C. ; Field, J.H. ; et al.
Phys.Lett.B 110 (1982) 329-334, 1982.
Inspire Record 169195 DOI 10.17182/hepdata.30996

The topology of hadronic e + e − annihilation events has been analysed using the sphericity tensor and a cluster method. Comparison with quark models including gluon bremsstrahlung yields good agreement with the data. The strong-coupling constant is determined in 1st order QCD to be α S =0.19±0.04 (stat) ± 0.04 (syst.) at 22 GeV and α S =0.16 ±0.02± 0.03 at 34 GeV. The differential cross section with respect to the energy fraction carried by the most energetic parton agrees with the prediction of QCD, but cannot be reproduced by a scalar gluon model. These results are stable against variations of the transverse momentum distribution of the fragmentation function within the quoted errors.

1 data table
Table 1

No description provided.


Measurement of the Anti-proton - Proton Total Cross-section and Elastic Scattering at the {CERN} Intersecting Storage Rings

Carboni, G. ; Kantardjian, G. ; Lloyd-Owen, D. ; et al.
Phys.Lett.B 108 (1982) 145-150, 1982.
Inspire Record 168349 DOI 10.17182/hepdata.31024

We measured the total cross section for p p scattering at √ s = 53 GeV at the CERN ISR. The method was based on the measurement of the total interaction rate and of the ISR luminosity. The result obtained, σ tot = 44.1 ± 2.0 mb, suggests that σ tot ( p p) starts increasing at ISR energies. A measurement of the p p differential cross section was also performed: the results show a change in the slope at | t | ≈ 0.1 GeV 2 , similar to that observed in pp scattering.

2 data tables
Table 1

No description provided.

Table 2

No description provided.


A Detailed Study of Average Charged Particle Multiplicity Versus Available Energy and Invariant Mass at Different $\sqrt{s}$ in $p p$ Interactions

Basile, M. ; Bonvicini, G. ; Cara Romeo, G. ; et al.
Nuovo Cim.A 67 (1982) 244, 1982.
Inspire Record 168751 DOI 10.17182/hepdata.37531

By using (pp) interactions at three different c.m. energies,\(\left( {\sqrt 8 } \right)_{pp} \)=30, 44, 62 GeV, it is shown that the average charged-particle multiplicity vs. the invariant mass of the hadronic systemm1,2 has the same behaviour as it hasvs. 2Ehad. Moreover, in both cases is shown to be nearly independent of\(\left( {\sqrt 8 } \right)_{pp} \) and in good agreement with the average charged-particle multiplicity measured in the (e+e−) annihilation.

10 data tables
Table 1

WITH SQRT(S) OF 30 GEV.

Table 2

WITH SQRT(S) OF 44 GEV.

Table 3

WITH SQRT(S) OF 62 GEV.

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Hadron Production by $e^+ e^-$ Annihilation at Center-of-mass Energies Between 2.6-{GeV} and 7.8-{GeV}. Part 2. Jet Structure and Related Inclusive Distributions

Hanson, G. ; Alam, M.S. ; Boyarski, A. ; et al.
Phys.Rev.D 26 (1982) 991, 1982.
Inspire Record 170499 DOI 10.17182/hepdata.38162

We present results on the jet structure observed in multihadronic events produced by e+e− annihilation in the Mark I magnetic detector at SPEAR. The evidence for jet structure and the jet-axis angular distribution are reported. We give inclusive distributions of the hadrons in Feynman x, rapidity, and transverse momentum relative to the jet axis.

19 data tables
Table 1

Observed particle PT with respect to jet axis for events with three or more detected charged particles.

Table 2

No description provided.

Table 3

No description provided.

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CHARGED PARTICLE MULTIPLICITY DISTRIBUTION IN anti-p p INTERACTIONS AT 22.4-GeV/c

The Dubna-Alma Ata-Helsinki-Kosice-Moscow-Prague-Tbilisi collaboration Batyunya, B.V. ; Boguslavsky, I.V. ; Gramenitsky, I.M. ; et al.
Sov.J.Nucl.Phys. 36 (1982) 234, 1982.
Inspire Record 169806 DOI 10.17182/hepdata.39549

None

1 data table
Table 1

No description provided.


Energy Dependence of Jet Measures in $e^+ e^-$ Annihilation

The PLUTO collaboration Berger, Christoph ; Genzel, H. ; Grigull, R. ; et al.
Z.Phys.C 12 (1982) 297, 1982.
Inspire Record 169193 DOI 10.17182/hepdata.16424

The jet character of the hadronic final states produced ine+e− annihilations is studied in terms of jet measures such as thrust, sphericity, jet opening angle and jet masses, in the energy range 7.7 to 31.6 GeV. All distributions and averages have been corrected for detector effects and initial state radiation. The energy dependence of the averages of these jet quantities is used to estimate the contributions due to perturbative QCD and fragmentation effects. Correlations between the jet measures and the multiplicity of charged hadrons are also presented.

12 data tables
Table 1

DIFFERENTIAL THRUST DISTRIBUTIONS WHERE THRUST IS MAX(SUM(ABS(PLONG))/SUM(ABS(P))).

Table 2

MEAN THRUST VALUES AS A FUNCTION OF CM ENERGY.

Table 3

DIFFERENTIAL SPERICITY DISTRIBUTIONS WHERE SPHERICITY IS 3/2*MIN(SUM(PT**2)/SUM(ABS(P))).

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Measurement of Energy Correlations in $e^+ e^- \to$ Hadrons

Schlatter, D. ; Abrams, G.S. ; Amidei, D. ; et al.
Phys.Rev.Lett. 49 (1982) 521, 1982.
Inspire Record 171070 DOI 10.17182/hepdata.20563

Energy correlations have been measured with the MARK II detector at the PEP storage ring (Stanford Linear Accelerator Center) at c.m. energy of 29 GeV and are compared to first-order QCD predictions. Fragmentation processes are significant and limit the precision with which the first-order strong-coupling constant can be determined.

2 data tables
Table 1

CORRELATION IS THE ENERGY WEIGHTED CROSS SECTION FOR OBSERVING THE ENERGY E1 IN THE SOLID ANGLE DOMEGA1 AND THE ANGLE E2 IN THE SOLID ANGLE DOMEGA2.SUMMED OVER ALL PAIRS OF PARTICLES IN DOMEGA1 AND DOMEGA2 AND ALL EVENTS.

Table 2

MEASUREMENT OF THE STRONG COUPLING CONSTANT.


A Study of Deep Inelastic Hadron - Hadron Collisions with a Large Acceptance Calorimeter Trigger

The Bari-Cracow-Liverpool-Munich-Nijmegen collaboration De Marzo, C. ; De Palma, M. ; Distante, A. ; et al.
Phys.Lett.B 112 (1982) 173-177, 1982.
Inspire Record 176541 DOI 10.17182/hepdata.34014

Large transverse energy cross sections of 300 GeV/ c pions and protons on hydrogen have been measured with a segmented calorimeter covering the central rapidity region −0.88 < y < 0.67 and 2 π in azimuth. The selected events show large multiplicities and no jet-like event structure. Processes more complicated than the scattering of two constituents appear to dominate these inelastic collisions.

8 data tables
Table 1

No description provided.

Table 2

No description provided.

Table 3

No description provided.

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SEARCH FOR NONSTRANGE BARYONIUM STATES IN THE BARYON EXCHANGE REACTION K- P ---> Y0 ANTI-P P AT 18.5-GeV/c

The BARI-BIRMINGHAM-CERN-MILAN-PARIS-PAVIA collaboration Armstrong, T. ; Baubillier, M. ; Beusch, W. ; et al.
Nucl.Phys.B 206 (1982) 185-192, 1982.
Inspire Record 184140 DOI 10.17182/hepdata.34058

Narrow baryonium production in the baryon exchange reactions K − p → Λ p p and K − p → pK − p p at 18.5 GeV/ c is investigated in a 12 events/nb experiment performed at the CERN Ω′ spectrometer. No narrow structure is observed in the p p mass spectra. Upper limits for production of baryonium states are given as a function of p p mass.

2 data tables
Table 1

'1'. (AP P) SYSTEM PRODUCED IN BACKWARD DIRECTION IN THE CMS.

Table 2

'1'. (AP P) SYSTEM PRODUCED IN BACKWARD DIRECTION IN THE CMS.


Inclusive Vector - Meson Production in the Central Region of $p p$ Collisions at $\sqrt{s}=63$-{GeV}

The Axial Field Spectrometer collaboration Akesson, T. ; Albrow, M.G. ; Almehed, S. ; et al.
Nucl.Phys.B 203 (1982) 27, 1982.
Inspire Record 176735 DOI 10.17182/hepdata.34135

Production of ϱ 0 , K ∗0 , K ∗0 , and φ have been measured in proton-proton collisions at the CERN Intersecting Storage Rings (ISR) at low p T in the central region. The transverse mass spectra are well described by exp (− aμ T ), with a = −6.4±0.2 GeV −1 . The cross sections for d σ/ d y| y=0 are 6.5±0.8±1.2 mb for ϱ 0 , 1.9±0.3±0.3 mb for K ∗) , 1.9±03±03 mb for K ∗0 , and 60.±0.12±0.13 mb for φ , where the first error is statistical and the second is sytematic.

2 data tables
Table 1

No description provided.

Table 2

No description provided.