Date

Measurement of the Reaction gamma gamma ---> pi+ pi+ pi- pi- at PETRA

The CELLO collaboration Behrend, H.J. ; Fenner, H. ; Schachter, M.J. ; et al.
Z.Phys.C 21 (1984) 205, 1984.
Inspire Record 191578 DOI 10.17182/hepdata.16344

We have determined the cross section for γγ→π+π+π−π− in a way free of assumptions about the relative contributions fromρ0ρ0,ρ02π and 4π (uncorrelated phase space). We find a sharp onset above threshold and a rather high cross section of about 200 nb aroundWγγ=1.5 GeV which consists to about 40% ofρ0ρ0 production with sizeable contributions fromρ02π and 4π (PS). The total cross section as well as theρ0ρ0 content fall rather fast at higher c.m. energies. Attempts to explain this behaviour in terms of production of known resonances are not successful so far. The angular distributions do not show any significant structure pointing to resonance formation in the 4π-system. Only theρ0-meson is observed in the moment analysis. The decay distributions of theρ0 for forward produced rhos are fairly consistent with helicity conservation of the produced rhos in accordance with the VDM picture.

5 data tables

No description provided.

RESULTS OF DECOMPOSITION OF THE CROSS SECTION INTO RHO RHO, RHO 2PI, AND 4PI(PHASE SPACE) USING TWO WIDE W BINS. SEE TEXT OF PAPER FOR DISCUSSION OF FITS.

RESULTS OF DECOMPOSITION OF THE CROSS SECTION INTO THE RHO RHO, RHO PI, AND 4PI (PHASE SPACE) USING SMALL W BINS. SEE TEXT OF PAPER FOR DISCUSSION OF FITS.

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Inclusive $\gamma$ and $\pi^0$ Production in $e^+ e^-$ Annihilation at 14-{GeV}, 22-{GeV}, and 34-{GeV} Center-of-mass Energy

The CELLO collaboration Behrend, H.J. ; Fenner, H. ; Schachter, M.J. ; et al.
Z.Phys.C 20 (1983) 207, 1983.
Inspire Record 191415 DOI 10.17182/hepdata.16318

We have measured the scale invariant inclusive photon and π0 cross sections atW=14, 22 and 34 GeV. A comparison with π± data shows no significant difference between neutral and charged pion production. Comparing the integrated cross sections in thex range 0.15<x<1.0 we observe a considerable decrease from 14 GeV to 34 GeV with a statistical significance of 1.5 standard deviations. This is compatible with the expectations for scaling violations from QCD.

8 data tables

NUMERICAL VALUES OF DATA SUPPLIED BY H. OBERLACK.

NUMERICAL VALUES OF DATA SUPPLIED BY H. OBERLACK.

NUMERICAL VALUES OF DATA SUPPLIED BY H. OBERLACK.

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Measurement of Production and Properties of Jets at the CERN anti-p p Collider

The UA2 collaboration Bagnaia, P. ; Banner, M. ; Battiston, R. ; et al.
Z.Phys.C 20 (1983) 117-134, 1983.
Inspire Record 191166 DOI 10.17182/hepdata.16305

The production and properties of high transverse momentum hadron jets have been measured in the UA2 experiment at the CERN\(\bar pp\) Collider\((\sqrt s= 540 GEV)\) using a highly segmented total absorption calorimeter. The characteristics of a sample of two-jet events with invariant mass up to 200 GeV/c2 are discussed, including measurements of their fragmentation properties, angular and rapidity distributions, and the properties of the additional energy clusters accompanying the two-jet system. Cross sections for inclusive jet production in the jet transverse momentum range between 30 and 100 GeV/c and for the two-jet invariant mass distribution in the mass range from 60–200 GeV/c2 are reported.

1 data table

No description provided.


Comparison of Inclusive Distributions in $p p$ and $\bar{p} p$ Interactions at $\sqrt{s}=53$-{GeV}

The Ames-Bologna-CERN-Dortmund-Heidelberg-Warsaw collaboration Breakstone, A. ; Campanini, R. ; Crawley, H.B. ; et al.
Phys.Lett.B 132 (1983) 458-462, 1983.
Inspire Record 191414 DOI 10.17182/hepdata.30631

Measurements are presented of inclusive distributions in pp and p p interactions at √ s = 53 GeV. The data were obtained at the CERN ISR using the Split Field Magnet spectrometer with a minimum bias trigger. The inclusive distributions are analyzed as functions of the transverse momentum, the rapidity and the Feynman- x variable.

4 data tables

No description provided.

No description provided.

No description provided.

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A Comparison of Charged Current Cross-sections and Structure Functions for Neutrino and Anti-neutrinos Beams on Hydrogen and Neon

The BEBC TST Neutrino collaboration Parker, M.A. ; Francois, T. ; Guy, J.G. ; et al.
Nucl.Phys.B 232 (1984) 1-20, 1984.
Inspire Record 192873 DOI 10.17182/hepdata.33899

Using BEBC equipped with a hydrogen-filled neon-surrounded track-sensitive target, the charged current cross sections and structure functions of hydrogen and neon targets traversed by the same neutrinos and antineutrinos are compared directly. The measured total cross-section ratios between hydrogen and neon allow precise total cross-section values for hydrogen to be inferred. Using this normalization, the ν and ν hydrogen data are combined and the quark distributions in free nucleons, parametrised as functions of ξ, are extracted. This free-nucleon parametrisation is then compared directly with the neon data in order to measure nuclear effects such as those recently reported by the EMC collaboration. Only small effects are seen, in excellent agreement with recent SLAC data in a more similar A and q 2 range.

3 data tables

Measured charged current total cross section.

Measured charged current total cross section.

AVERAGE Q**2 IS 6.9GEV**2 FOR NU AND 4.3GEV**2 FOR ANU.


Measurement of Transverse Momenta in $e^+ e^-$ Annihilation Jets at {PETRA}

The PLUTO collaboration Berger, Christoph ; Genzel, H. ; Lackas, W. ; et al.
Z.Phys.C 22 (1984) 103, 1984.
Inspire Record 191161 DOI 10.17182/hepdata.16268

Transverse particle momenta have been measured ine+e− annihilation into hadrons at c.m. energies between 9.4 and 31.6 GeV. The data are fully corrected for detector effects and radiation in the initial state. A comparison is made with recent QCD calculations.

3 data tables

MEASUREMENTS MADE WITH RESPECT TO THE SPHERICITY AXIS.

MEASUREMENTS MADE WITH RESPECT TO THE THRUST AXIS.

MEASUREMENTS MADE WITH RESPECT TO THE MOST ENERGETIC PARTON AXIS.


A Comparison of Hadron Production in $p \bar{p}$ and $p p$ Collisions in the Central Region at $\sqrt{s}=53$-{GeV}

The Axial Field Spectrometer collaboration Akesson, T. ; Albrow, M.G. ; Almehed, S. ; et al.
Nucl.Phys.B 228 (1983) 409-423, 1983.
Inspire Record 190653 DOI 10.17182/hepdata.37131

We have studied the inclusive production of the hadrons π ± , K ± , p, p , Λ, Λ , ρ and ⋉ in the central region at the ISR s = 53 GeV , in both pp and p p collisions. Differences are observed only for K ± , p, and p production. We then study also correlations between low- p T pp and p p pairs in the two types of collisions, separating the contribution from baryon pair production and from the incident particles (stopping protons). We observe a positive correlation between two stopping protons; between the production of two pairs, and between a stopping proton and a pair production, there are negative correlations.

1 data table

No description provided.


Bose-einstein Correlations in $\alpha \alpha$, $p p$ and $p \bar{p}$ Interactions

The Axial Field Spectrometer collaboration Akesson, T. ; Albrow, M.G. ; Almehed, S. ; et al.
Phys.Lett.B 129 (1983) 269-272, 1983.
Inspire Record 190654 DOI 10.17182/hepdata.30661

Bose-Einstein correlations between pions produced in the central region of rapidity in αα, pp and p p interactions have been studied at the ISR. The parameters r and τ c -often interpreted as the radius and depth of the π-emitting region - are found to be independent of incident particle type but to depend on the mean charged multiplicity. In high multiplicity events, the pions appear to originate from a larger space-time region.

12 data tables

FOR DEFINITION OF R++ SEE PAPER.

FOR DEFINITION OF R++ SEE PAPER.

FOR DEFINITIONS OF R++ AND TAU*C SEE PAPER.

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Experimental J/psi Hadronic Production from 150-GeV/c to 280-GeV/c

The NA3 collaboration Badier, J. ; Boucrot, J. ; Bourotte, J. ; et al.
Z.Phys.C 20 (1983) 101, 1983.
Inspire Record 191240 DOI 10.17182/hepdata.2212

A detailed study ofJ/ψ hadronic production has been performed in a high statistics experiment (more than 1.5 106J/ψ observed in their dimuon decay mode). Data have been taken with incident π±,K±,p±, on hydrogen and platinum targets, at 150, 200 and 280 GeV/c. We find from the observed nuclear dependance of the cross sections, that about 18% of theJ/ψ are produced diffractively. Using known structure functions of the quarks in the nucleon and in the pion, we derive estimations for the gluon structure functions.

11 data tables

No description provided.

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Multiplicity Distributions in $\alpha \alpha$ and $\alpha p$ Collisions at the {CERN} {ISR}

The CERN-Heidelberg-Lund collaboration Bell, W. ; Braune, K. ; Claesson, G. ; et al.
Phys.Lett.B 128 (1983) 349-353, 1983.
Inspire Record 190332 DOI 10.17182/hepdata.30673

The multiplicities of charged secondaries from inelastic αp and αα collisions have been measured using the Split-Field Magnet detector at the CERN Intersecting Storage Rings. Corrected multiplicity distributions for αα and αp interactions are compared with those for pp interactions and with theoretical predictions.

2 data tables

No description provided.

No description provided.