Feltham, A.
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Production of Phi and omega mesons in near-threshold p p reactions.

The DISTO collaboration Balestra, F. ; Bedfer, Y. ; Bertini, R. ; et al.
Phys.Rev.Lett. 81 (1998) 4572-4575, 1998.
Inspire Record 481641 DOI 10.17182/hepdata.19496

The ratio of the exclusive production cross sections for φ and ω mesons has been measured in pp reactions at Tbeam=2.85GeV. The observed φ/ω ratio is (3.7±0.7−0.9+1.2)×10−3. After phase space corrections, this ratio is about a factor of 10 enhanced relative to naive predictions based upon the Okubo-Zweig-Iizuka rule, in comparison to an enhancement by a factor of ∼3 previously observed at higher energies. The modest increase of this enhancement near the production threshold is compared to the much larger increase of the φ/ω ratio observed in specific channels of p¯p annihilation experiments.

1 data table
Table 1

No description provided.


Differential cross section of the p n --> p p(1)S(0)) pi- reaction extracted from p d --> p p p pi-.

Duncan, F. ; Hahn, H. ; Aclander, C. ; et al.
Phys.Rev.Lett. 80 (1998) 4390-4393, 1998.
Inspire Record 471244 DOI 10.17182/hepdata.19508

The double differential cross section for pn→pp(1S0)π− at three beam energies has been extracted from the quasifree process pd→pppπ−. A comparison is carried out with single differential cross section measurements for 3He(π−,pn)n, where the pion is thought to be absorbed onto a pp(1S0) “diproton” state. A significant difference is observed in the shape of the angular distribution between the production and absorption data. This difference is ascribed to the effects of the 3He nuclear environment characterizing the absorption process; however, an adequate theoretical explanation is not available.

3 data tables
Table 1

Only statistical errors are given in the table. Final P P system is in 1S0 ((2S+1) L J) state.

Table 2

Only statistical errors are given in the table. Final P P system is in 1S0 ((2S+1) L J) state.

Table 3

Only statistical errors are given in the table. Final P P system is in 1S0 ((2S+1) L J) state.


Search for psi(2S) production in e+ e- annihilations at 4.03-GeV

The BES collaboration Bai, J.Z. ; Bian, J.G. ; Blum, I. ; et al.
Phys.Rev.D 57 (1998) 3854-3859, 1998.
Inspire Record 468969 DOI 10.17182/hepdata.22270

A search is performed for the production of the ψ(2S) in e+e− annihilation at a center-of-mass energy of 4.03 GeV using the BES detector operated at the Beijing Electron Positron Collider (BEPC). The kinematic features of the reconstructed ψ(2S) signal are consistent with its being produced only in association with an energetic photon resulting from initial state radiation (ISR). Limits are placed on ψ(2S) production from the decay of unknown charmonia or metastable hybrids that might be produced in e+e− annihilations at 4.03 GeV. Under the assumption that the observed cross section for ψ(2S) production is due entirely to ISR, the partial width Γee of the ψ(2S) is measured to be 2.07±0.32keV.

1 data table
Table 1

PSI(UNSPEC) is considered as a new 3D2 charmonium state. CHI/C(UNSPEC) is considered as any unknown charmonium state. EXOTIC is considered as a metastable hybrid.


Phi emission in central Pb + Pb collisions at 158-GeV/u.

The NA49 collaboration Pühlhofer, Falk ; Appelshäuser, H. ; Bächler, J. ; et al.
Nucl.Phys.A 638 (1998) 431-434, 1998.
Inspire Record 481889 DOI 10.17182/hepdata.36218

Data on φ -production obtained by the CERN NA49 experiment for central Pb+Pb collisions at 158 GeV/u are presented. Compared with pp interactions the φ -yield shows substantial strangeness enhancement: the φ /π ratio is found to increase by a factor of 2.6 ± 0.6, which is approximately the square of the K/π enhancement.

2 data tables
Table 1

5% most central collosions, MT - M0 = 0 - 1.4 GeV, preliminary data.

Table 2

5% most central events.


Tensor analyzing power Ayy of d-p radiative capture

Anklin, H. ; de Bever, L.J. ; Buttazzoni, S. ; et al.
Nucl.Phys.A 636 (1998) 189-206, 1998.
Inspire Record 487232 DOI 10.17182/hepdata.36233

Proton-deuteron radiative capture has been studied with polarized deuterons at a laboratory deuteron energy E d = 45 MeV. Precise data for the tensor analyzing power A yy have been measured in the angular range 50° to 160°. Three-nucleon Faddeev wave functions in the initial scattering and final bound state are calculated using realistic nucleon-nucleon potentials. Mesonic exchange currents are included according to Siegert's theorem. Comparison to other recent experimental data is performed as well.

1 data table
Table 1

No description provided.


Kaon and proton ratios from central Pb + Pb collisions at the CERN SPS.

The NA44 collaboration Kaneta, M. ; Bearden, I.G. ; Bøggild, H. ; et al.
Nucl.Phys.A 638 (1998) 419-422, 1998.
Inspire Record 481886 DOI 10.17182/hepdata.36250

K − /K + and p ¯ / p ratios measured in 158 A·GeV Pb+Pb collisions are shown as a function of transverse momentum P T and centrality in top 8.5% central region. Little centrality dependence of the K − / K + and p ¯ / p ratios is observed. The transverse mass m T distribution and dN/dy of K + , K − , p and p ¯ around mid-rapidity are obtained. The temperature T ch and the chemical potentials for both light and strange quarks (μ q , μ s ) at chemical freeze-out are determined by applying simple thermodynamical model to the present data. The resultant μ q , μ s and T ch are compared with those obtained from similar analysis of SPS S+A and AGS Si+A data. The chemical freeze-out temperature T ch at CERN energies is higher than thermal freeze-out temperature T fo which is extracted from m T distribution of charged hadrons. At AGS energies T ch is close to T fo .

2 data tables
Table 1

Data obtained from the fit of MT spectra.

Table 2

Data obtained from the fit of MT spectra.


Thermal multifragmentation in p + Au interactions at 2.16-GeV, 3.6-GeV and 8.1-GeV incident energies.

Avdeev, S.P. ; Karnaukhov, V.A. ; Kuznetsov, V.D. ; et al.
Eur.Phys.J.A 3 (1998) 75-83, 1998.
Inspire Record 479490 DOI 10.17182/hepdata.43488

Multiple emission of intermediate-mass fragments has been studied for the collisions p + Au at 2.16, 3.6 and 8.1 GeV with the FASA setup. The mean IMF multiplicities for events with at least one IMF a

1 data table
Table 1

No description provided.


Backward slow protons production in the inelastic interactions of Li-6 and Li-7 nuclei with emulsion nuclei at Dubna energy.

El-Nadi, M. ; Abdelsalam, A. ; Ali-Mossa, N. ; et al.
Eur.Phys.J.A 3 (1998) 183-195, 1998.
Inspire Record 480319 DOI 10.17182/hepdata.43531

We report the experimental measurements on the multiplicity of slow target associated particles, in the forward (θlab≤ 90°) and backward (θlab > 90°) hemispheres, and the different correlations betwee

4 data tables
Table 1

No description provided.

Table 2

No description provided.

Table 3

No description provided.

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Kinetic energy spectrum and polarization of neutrons from the reaction C-12(p(pol.),n(pol.))X at 590-MeV.

Arnold, J. ; van den Brandt, B. ; Daum, M. ; et al.
Eur.Phys.J.A 2 (1998) 411-415, 1998.
Inspire Record 477089 DOI 10.17182/hepdata.43498

The kinetic energy spectrum and the polarization of the PSI neutron beam produced in the reaction 12C(p,n)X at 0° with 590 MeV polarized protons were investigated. A strong energy dependence of the ne

1 data table
Table 1

No description provided.


Angular dependence of p p spin correlation and rescattering observables between 1.80-GeV and 2.10-GeV.

Allgower, C.E. ; Ball, J. ; Barabash, L.S. ; et al.
Eur.Phys.J.C 1 (1998) 131-138, 1998.
Inspire Record 465999 DOI 10.17182/hepdata.43398

A polarized proton beam extracted from SATURNE II and the Saclay polarized proton target were used to determine the spin correlation parameter Aoosk and the rescattering observablesKos″ so; Dos″ok, Nos″sn, andNonsk at 1.80 and 2.10 GeV. The beam polarization was oriented perpendicular to the beam direction in the horizontal scattering plane and the target polarization was directed either along the vertical axis or longitudinally. Left-right and up-down asymmetries in the second scattering were measured. A check for the beam optimization with the beam and target polarizations oriented vertically provided other observables, of which results forDonon andKonno at 1.80, 1.85, 2.04, and 2.10 GeV are listed here. The new data at 2.10 GeV suggest a smooth energy dependence of spin triplet scattering amplitudes at fixed angles in the vicinity of this energy.

13 data tables
Table 1

Spin correlation parameter CSL measured with the beam polarisation measuredalong the +-S direction and the target polarisation along the +-L axis. Additional 4.3 PCT systematic normalisation uncertainty.

Table 2

Measurement of the rescattering parameter KSS with the beam polarisation inthe +- S direction. Additional 6.7 PCT systematic error.

Table 3

Measurement of the rescattering parameter KSS with the beam polarisation inthe +- S direction. Additional 6.7 PCT systematic error.

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