von Dardel, G.
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PHOTON DIFFRACTIVE DISSOCIATION TO rho rho pi AND rho pi pi pi STATES

The Omega Photon collaboration Atkinson, M. ; Axon, T.J. ; Barberis, D. ; et al.
Z.Phys.C 38 (1988) 535, 1988.
Inspire Record 261249 DOI 10.17182/hepdata.48824

This paper reports studies of the reactions γp→ρ π π πp and γp→ρ ρ πp. In particular a peak is reported in the ρ ρ π mass spectrum with closely similar mass and width to those of the ω ρ π peak previously reported in the reaction γp→ω ρ πp. The ratio of production cross sections is found to be ρ ρ π/ω ρ π=0.96±0.19, in serious disagreement with the expectation from Vector Meson Dominance. A possible explanation is indicated.

2 data tables
Table 1

No description provided.

Table 2

Numerical values requested from authors.


The Production of $J/\psi$ in 200-{GeV}/a Oxygen - Uranium Interactions

The NA 38 collaboration Abreu, M.C. ; Alimi, M. ; Baglin, C. ; et al.
Z.Phys.C 38 (1988) 117, 1988.
Inspire Record 261007 DOI 10.17182/hepdata.29826

The dimuon production in 200 GeV/nucleon oxygen-uranium interactions is studied by the NA 38 Collaboration. The production ofJ/ψ, correlated with the transverse energyET, is investigated and compared to the continuum, as a function of the dimuon massM and transverse momentumPT. A value of 0.64±0.06 is found for the ratio (ψ/Continuum at highET)/(ψ/Continuum at lowET), from which theJ/ψ relative suppression can be extracted. This suppression is enhanced at lowPT.

1 data table
Table 1

Ratio of number of J/PSI's to number of continuum events in given mass interval.


Observation of Inclusive $B$ Meson Decays Into $\Lambda(c$)+ Baryons

The ARGUS collaboration Albrecht, H. ; Bockmann, P. ; Glaser, R. ; et al.
Phys.Lett.B 210 (1988) 263-266, 1988.
Inspire Record 260762 DOI 10.17182/hepdata.29928

We report the first direct observation of B meson decays into Λ c + baryons using the decay channel Λ c + → pK − π + . The product of branching ratios Br(B→Λ c + X)·Br(Λ c + →pK − π + = (0.30±0.12±0.06)% is derived from an observed signal of 208±89 events. Using previous measurements of inclusive baryon rates we find a branching ratio for Λ c + → pK − π + of (4.1±2.4)%. The measured Λ c + momentum spectrum indicates that the multi-particle final states dominate the decay B→Λ c + X.

1 data table
Table 1

ACCEPTANCE CORRECTED.


rivet Analysis
A Search for $\omega \phi$ and $\phi \phi$ Production in the Reactions $\gamma \gamma \to K^+ K^- \pi^+ \pi^- \pi^0$ and $\gamma \gamma \to 2 K^+ 2 K^-$

The ARGUS collaboration Albrecht, H. ; Bockmann, P. ; Glaser, R. ; et al.
Phys.Lett.B 210 (1988) 273-277, 1988.
Inspire Record 260828 DOI 10.17182/hepdata.29918

The reaction γγ→K + K − π + π − π 0 has been observed for the first time, using the ARGUS detector at the e + e − storage ring DORIS II at DESY. The cross section shows an enhancement for W γγ close to 3 GeV/ c 2 . Searches for γγ→ωφ and for γγ→φφ leading to this final state, as well as for γγ→φφ→2K + 2K − , have been performed. The derived upper limits for ωφ and φφ production are compatible with q q q q model predictions.

2 data tables
Table 1

TOPOLOGICAL CROSS SECTION.

Table 2

95 PCT CL UPPER LIMITS.


Observation of the Charmed Baryon $\Lambda(c$) in $e^+ e^-$ Annihilation at 10-{GeV}

The ARGUS collaboration Albrecht, H. ; Bockmann, P. ; Glaser, R. ; et al.
Phys.Lett.B 207 (1988) 109-114, 1988.
Inspire Record 260826 DOI 10.17182/hepdata.29980

Using the ARGUS detector at DORIS II, we have studied the production of the charmed baryon Λ c in e + e − annihilation at centre-of-mass energies near 10 GeV. The Λ c + was seen in the three decay modes pK − π + , Λπ + π − π + and K̄ 0 p, with products of normalized cross section times branching ratio [ R ·Br] of (10.8±1.4±1.2)×10 −3 , 6.6±1.5±0.9)×10 −3 and (6.7±1.4±0.8)×10 −3 respectively. The measured mass for the Λ c was (2283.1±1.7±2.0) MeV/ c 2 . A limit on the decay rates to Λπ + is reported. The fragmentation function of the Λ c was measured.

2 data tables
Table 1

Data requested from authors.

Table 2

No description provided.


Two Particle Correlations in 360-{GeV}/$c $p p Interactions

The EHS-RCBC collaboration Bailly, J.L. ; Banerjee, S. ; Bruyant, F. ; et al.
Z.Phys.C 40 (1988) 13, 1988.
Inspire Record 261311 DOI 10.17182/hepdata.15605

Two particle correlations of hadrons produced in 360 GeV/cpp interactions are investigated in the transverse plane and in rapidity. The data were obtained at the European hybrid spectrometer equipped with a rapid cycling bubble chamber. The observed transverse and rapidity correlations are compared with the one string LUND-and a two string dual parton-model. These models predict in general stronger correlations in the transverse plane and much weaker correlations in rapidity than found in the data. The LUND-FRITIOF-and multichain dual parton models provide a better reproduction of the data, although the agreement is not yet satisfactory. Only the UA5 cluster model GENCL shows agreement with the data.

1 data table
Table 1

No description provided.


Comparison of the Particle Flow in $q \bar{q} \gamma$ and $q \bar{q} g$ Events From $e^+ e^-$ Annihilations at {PETRA}

The JADE collaboration Saada, F.Ould ; Allison, J. ; Ambrus, K. ; et al.
Z.Phys.C 39 (1988) 1, 1988.
Inspire Record 260834 DOI 10.17182/hepdata.15623

The particle flow distributions in the event plane of 3-jet\((e^ +e^ -\to q\bar qg)\) and of radiative 2-jet\((e^ +e^ -\to q\bar q\gamma )\) events are compared at a centre of mass energy of 35 GeV. The number of particles in the angular region opposite to the gluon in\(q\bar qg\) events is found to be significantly reduced relative to the number of particles in the region opposite to the hard photon in\(q\bar q\gamma \) events. This depletion is expected from the “string effect” observed in 3-jet events. It can be explained within the framework of QCD as arising from soft gluon interference.

1 data table
Table 1

Data requested from authors.


Measurement of the Difference in R = $\sigma^-$l / $\sigma^-$t and $\sigma$(a) / $\sigma(D$) in Deep Inelastic $e D$, $e$ Fe and $e$ Au Scattering

Dasu, S. ; de Barbaro, P. ; Bodek, A. ; et al.
Phys.Rev.Lett. 60 (1988) 2591, 1988.
Inspire Record 260760 DOI 10.17182/hepdata.20155

We measured the differences in R=σLσT and the cross-section ratio σAσD in deep-inelastic electron scattering from D, Fe, and Au nuclei in the kinematic range 0.2≤x≤0.5 and 1≤Q2≤5 (Gev/c)2. Our results for RA−RD are consistent with zero for all x and Q2, indicating that possible contributions to R from nuclear higher-twist effects and spin-0 constituents in nuclei are not different from those in nucleons. The European Muon Collaboration effect is reconfirmed, and the low-x data from all recent experiments, at all Q2, are now in agreement.

4 data tables
Table 1

No description provided.

Table 2

No description provided.

Table 3

No description provided.

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OBSERVATION OF psi PRODUCTION IN e+ e- ANNIHILATION AT 29-GeV

Wormser, G. ; Ong, R.A. ; Abrams, G.S. ; et al.
Phys.Rev.D 38 (1988) 1001, 1988.
Inspire Record 260717 DOI 10.17182/hepdata.18617

Inclusive ψ production in e+e− annihilation at 29 GeV has been measured with the Mark II detector. The ψ cross section is found to be 1.1±0.5±0.4 pb. After subtraction of the expected contribution from B decay, an upper limit of 0.02σμμ is obtained for other sources of ψ production.

1 data table
Table 1

No description provided.


Inclusive production of $\varrho^{0}$ and f$_{2}$ mesons in $\pi^{-}p$ interactions at 360 GeV/c

The LEBC-EHS collaboration Bailly, J.D. ; Verbeure, F. ; Banerjee, S. ; et al.
Yad.Fiz. 49 (1989) 1014-1020, 1989.
Inspire Record 262830 DOI 10.17182/hepdata.10426

None

10 data tables
Table 1

No description provided.

Table 2

No description provided.

Table 3

No description provided.

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