Date

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

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

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10 data tables

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Production of Low Transverse Energy Clusters in anti-p p Collisions at s**(1/2) = 0.2-TeV to 0.9-TeV and their Interpretation in Terms of QCD Jets

The UA1 collaboration Albajar, C. ; Albrow, M.G. ; Allkofer, O.C. ; et al.
Nucl.Phys.B 309 (1988) 405-425, 1988.
Inspire Record 261009 DOI 10.17182/hepdata.33326

The production of transverse energy clusters in minimum bias proton-antiproton collisions at the CERN SPS Collider is studied with the UA1 detector over a new range of centre of mass energies (√ s = 0.2−0.9 TeV). This study is intended to investigate how low in transverse momentum perturbative QCD is able to describe the dynamics of hadron collisions. We observe that clusters with transverse energy in excess of a few GeV exhibit properties in agreement with QCD expectations for parton scattering, supporting their interpretation in terms of jet production. We find that the jet-event rate represents a sizeable fraction of the inelastic rate and is increasing with √ s over the measured energy range.

8 data tables

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Evidence for Anomalous Prompt Photons in Deep Inelastic Muon Scattering at 200-{GeV}

The European Muon collaboration Aubert, J.J. ; Bassompierre, G. ; Becks, K.H. ; et al.
Phys.Lett.B 218 (1989) 248-256, 1989.
Inspire Record 261250 DOI 10.17182/hepdata.29855

The inclusive yield of photons has been measured from deep inelastic interactions of 200 GeV muons on hydrogen. After subtracting the contributions from hadron electromagnetic decays and Bethe-Heitler muon bremsstrahlung, residual photons are observed at low p T and low z at a mean level of 0.15±0.06 per interaction. The quark Compton scattering process is unable to explain the data, thus indicating an anomalous photon production.

2 data tables

Z distribution of anomalous direct photons.

PT distribution of anomalous direct photons.


Determination of $\gamma (e e$) of the $\Upsilon$ (1s) and $\Upsilon$ (2s) Resonances and Measurement of R at $W=9$.39-{GeV}

The Crystal Ball collaboration Jakubowski, Z. ; Antreasyan, D. ; Bartels, H.W. ; et al.
Z.Phys.C 40 (1988) 49, 1988.
Inspire Record 261078 DOI 10.17182/hepdata.15560

Using the Crystal Ball detector operating at the DORIS II storage ring we have measured the leptonic partial widthsГeeof the Υ(1S) and Υ(2S) reson

1 data table

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$\eta$ and $\eta^\prime$ Production in $e^+ e^-$ Annihilation at 29-{GeV}: Indications for the $D(s$)+- Decays Into $\eta \pi^\pm$ and $\eta^\prime \pi^\pm$

Wormser, G. ; Abrams, G.S. ; Amidei, D. ; et al.
Phys.Rev.Lett. 61 (1988) 1057, 1988.
Inspire Record 261194 DOI 10.17182/hepdata.20080

η production has been investigated by the Mark II collaboration at the SLAC e+e− storage ring PEP. η particles are reconstructed by their γγ decay mode. The η fragmentation function has been measured and found to be in good agreement with the Lund-model prediction. η′ production has been measured for the first time in high-energy e+e− annihilation. There is evidence at the 3σ level for Ds± decay into ηπ± and η′π±.

4 data tables

Numerical values supplied by G.Wormser.

Z = 0.0 point extrapolated using LUND fragmentation model.

Z = 0.0 point extrapolated using LUND fragmentation model.

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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

No description provided.

Numerical values requested from authors.


Low Mass Dimuon Production at the {CERN} Proton - Anti-Proton Collider

The UA1 collaboration Albajar, C. ; Albrow, M.G. ; Allkofer, O.C. ; et al.
Phys.Lett.B 209 (1988) 397-406, 1988.
Inspire Record 261359 DOI 10.17182/hepdata.29936

We present a study of low mass dimuon events [ m ( μμ ) < 6 GeV/ c 2 ] from the UA1 experiment at the CERN p p collider. Contributions from semileptonic decays of heavy flavour particles, Drell-Yan type processes, J/ψ decays and leptonic decays of light mesons are extracted, and cross sections for high p T beauty and Drell-Yan production are derived. A limit for the branching fraction for the exotic decay B 0 →μ + μ − is also obtained. The cross section for section for low mass, high p T Drell-Yan prod uction is compared to the measured direct photon cross section using QED and QCD derived relationship. This relationship is used to infer a measurement of the single photon cross section at lower values of transverse momentum, where photons cannot be unambigously identified.

1 data table

GLOBAL SYTEMATIC ERROR OF 30PCT HAS TO BE ADDED.


Some Properties of Charmed Particles Produced in Nucleus Interactions

Aoki, S. ; Arnold, R. ; Baroni, G. ; et al.
Phys.Lett.B 209 (1988) 113-118, 1988.
Inspire Record 261774 DOI 10.17182/hepdata.29940

The azimuthal correlation distribution of 102 charmed-particle pairs observed in the hybrid emulsion experiment WA75 is compared with theoretical predictions. The various pairs - (D − D 0 ), (D − D + ), (D 0 D 0 ) and (D + D 0 )-all s how, within statistical error, the same azimuthal correlation distribution, demonstrating its independence from the specific nature of the production channel. Among the decays of 150 charged charmed particles and 138 neutral ones seen, higher multiplicities are favoured for hadronic as opposed to semileptonic decays. The data are consistent with the muonic decays of charged D mesons proceeding through the channels (μ ± , v, K 0 ) and [μ ± , v, K ∗0 (892)] , the fraction through K 0 being 0.76±0.06.

5 data tables

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Two Jet Mass Distributions at the {CERN} Proton - Anti-Proton Collider

The UA1 collaboration Albajar, C. ; Albrow, M.G. ; Allkofer, O.C. ; et al.
Phys.Lett.B 209 (1988) 127-134, 1988.
Inspire Record 261782 DOI 10.17182/hepdata.29947

Two-jet mass distributions have been measured as a function of centre-of-mass scattering angle for high-mass jet pairs produced in proton-antiproton collisions at the CERN collider operating at a centre-of-mass energy of 630 GeV. The agreement between QCD expectations and the experimental measurements has been used to place limits on the production cross section of an object X decaying into two jets. In particular we consider the existence of a massive colour octet of vector gauge bosons (axigluons). We exclude axigluons with a width Λ A < 0.4 m A and a mass m A in the range 150 < m A < 310 GeV/ c 2 (95% CL).

1 data table

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