Gialas, I.
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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 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.


Production of the D(s)+- by High-Energy Neutrons

Shipbaugh, C. ; Wiss, J. ; Binkley, M. ; et al.
Phys.Rev.Lett. 60 (1988) 2117, 1988.
Inspire Record 23063 DOI 10.17182/hepdata.20174

We have observed the production of the Ds± by a high-energy neutron beam on nuclear targets. The Ds± was observed in the decay mode Ds±→φπ±, φ→K+K−. The average of the inclusive cross sections for Ds+ and Ds− hadroproduction is measured to be BdσdxF=2.85±0.80±0.86 μb/nucleon at xF=0.175 on the assumption of a linear A dependence, where B≡Γ(Ds±→φπ±)Γ(Ds±→all).

1 data table
Table 1

No description provided.


rivet Analysis
$\eta$ 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
Table 1

Numerical values supplied by G.Wormser.

Table 2

Z = 0.0 point extrapolated using LUND fragmentation model.

Table 3

Z = 0.0 point extrapolated using LUND fragmentation model.

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Measurement of Spin Effects in $p$ (Polarized) $p$ (Polarized) $\to p p$ at 18.5-{GeV}/$c$

Crabb, D.G. ; Gialas, I. ; Krisch, A.D. ; et al.
Phys.Rev.Lett. 60 (1988) 2351, 1988.
Inspire Record 261135 DOI 10.17182/hepdata.20096

We measured the analyzing power A and the spin-spin correlation parameter Ann in medium-P⊥2 proton-proton elastic scattering, using a polarized-proton target and the 18.5-GeV/c Brookhaven Alternating-Gradient Synchrotron polarized-proton beam. We found sharp dips in both A and Ann, which occur at different P⊥2 values. The unexpected sharp structure in the spin-spin force occurs near P⊥2=2.3 (GeV/c)2 where the elastic cross section has no apparent structure.

1 data table
Table 1

Errors contain both statistics and systematics.


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
Table 1

No description provided.

Table 2

No description provided.

Table 3

No description provided.

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rivet Analysis
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
Table 1

No description provided.


The Acceleration of Polarized Protons to 22-{GeV}/$c$ and the Measurement of Spin Spin Effects in $p$ (Polarized) + $p$ (Polarized) $\to p + p$

Khiari, F.Z. ; Cameron, P.R. ; Court, G.R. ; et al.
Phys.Rev.D 39 (1989) 45, 1989.
Inspire Record 262472 DOI 10.17182/hepdata.23245

Accelerating polarized protons to 22 GeV/c at the Brookhaven Alternating Gradient Synchro- tron required both extensive hardware modifications and a difficult commissioning process. We had to overcome 45 strong depolarizing resonances to maintain polarization up to 22 GeV/c in this strong-focusing synchrotron. At 18.5 GeV/c we measured the analyzing power A and the spin-spin correlation parameter Ann in large- P⊥2 proton-proton elastic scattering, using the polarized proton beam and a polarized proton target. We also obtained a high-precision measurement of A at P⊥2=0.3 (GeV/c)2 at 13.3 GeV/c. At 18.5 GeV/c we found that Ann=(-2±16)% at P⊥2=4.7 (GeV/c)2, where it was about 60% near 12 GeV at the Argonne Zero Gradient Synchrotron. This sharp change suggests that spin-spin forces may have a strong and unexpected energy dependence at high P⊥2.

3 data tables
Table 1

No description provided.

Table 2

2.2 GeV point taken from Brown et al., PR D31(85) 3017.

Table 3

No description provided.


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
Table 1

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
Table 1

No description provided.

Table 2

No description provided.

Table 3

No description provided.

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