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Energy dependence of pion and kaon production in central Pb + Pb collisions.

The NA49 collaboration Afanasiev, S.V. ; Anticic, T. ; Barna, D. ; et al.

Phys.Rev.C 66 (2002) 054902, 2002.

Inspire Record 586383 DOI 10.17182/hepdata.31729

Measurements of charged pion and kaon production in central Pb+Pb collisions at 40, 80 and 158 AGeV are presented. These are compared with data at lower and higher energies as well as with results from p+p interactions. The mean pion multiplicity per wounded nucleon increases approximately linearly with s_NN^1/4 with a change of slope starting in the region 15-40 AGeV. The change from pion suppression with respect to p+p interactions, as observed at low collision energies, to pion enhancement at high energies occurs at about 40 AGeV. A non-monotonic energy dependence of the ratio of K^+ to pi^+ yields is observed, with a maximum close to 40 AGeV and an indication of a nearly constant value at higher energies.The measured dependences may be related to an increase of the entropy production and a decrease of the strangeness to entropy ratio in central Pb+Pb collisions in the low SPS energy range, which is consistent with the hypothesis that a transient state of deconfined matter is created above these energies. Other interpretations of the data are also discussed.

33 data tables

Table 1

The centrality of the collisions expressed as a percentage of the inelastic cross section (7.15nb), and the mean numbers of wounded nuclei.

Table 2

The inverse slope parameter of the fitted transverse mass spectra.

Table 3

The rapidity density averaged over the rapidity interval -0.6 to 0.6.

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WA97 results on strangeness production in lead lead collisions at 158-A-GeV/c

The WA97 collaboration Andersen, E. ; Andrighetto, A. ; Antinori, F. ; et al.

Nucl.Phys.A 610 (1996) 165C-174C, 1996.

Inspire Record 432744 DOI 10.17182/hepdata.36503

Preliminary results from WA97 measurements on Λ, Ξ and Ω production in lead-lead and proton-lead collisions are presented, along with a comparison of WA97 proton-lead data with previous WA85 proton-tungsten results. The ratio Ω gX seems to be enhanced in lead initiated reactions compared to proton initiated reactions.

4 data tables

Table 1

No description provided.

Table 2

No description provided.

Table 3

PRELIMINARI DATA.

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Hadron yields and hadron spectra from the NA49 experiment

The NA49 collaboration Jones, P.G. ; Afanasiev, S.V. ; Alber, T. ; et al.

Nucl.Phys.A 610 (1996) 188C-199C, 1996.

Inspire Record 432742 DOI 10.17182/hepdata.36468

Preliminary inclusive spectra of negative hadrons, net protons and neutral strange particles are presented, measured by the NA49 experiment in central Pb+Pb collisions at 158 GeV per nucleon. Comparison of their yields with those from the lighter S+S system suggests that the yields scale approximately with the number of participating nucleons.

4 data tables

Table 1

CENTRAL COLLISIONS, PRELIMINARY DATA.

Table 2

CENTRAL COLLISIONS, PRELIMINARY DATA.

Table 3

CENTRAL COLLISIONS, PRELIMINARY DATA.

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Strange particle production in sulphur - tungsten interactions at 200-GeV/c per nucleon

The WA85 collaboration Kinson, J.B. ; Abatzis, S. ; Antinori, F. ; et al.

Nucl.Phys.A 544 (1992) 321-334, 1992.

Inspire Record 321220 DOI 10.17182/hepdata.36664

Multi-strange baryon and anti-baryon production is expected to be a useful probe in the search for Quark-Gluon Plasma formation. We present the transverse mass distributions of negative particles, K o s, Λs, Λ s, and Ξ − s produced in sulphurtungsten interactions at 200 GeV/c per nucleon and give the corrected ratios Λ Λ, Ξ − Λ and Ξ − /Λ . We note that our ratio Ξ − / Λ appears large in comparison to that from p p interactions.

4 data tables

Table 1

No description provided.

Table 2

No description provided.

Table 3

No description provided.

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Hadron production in S + Ag and S + Au collisions at 200-GeV/nucleon

The NA35 collaboration Röhrich, Dieter ; Alber, T. ; Bächler, J. ; et al.

Nucl.Phys.A 566 (1994) 35C-44C, 1994.

Inspire Record 378631 DOI 10.17182/hepdata.36563

None

3 data tables

Table 1

No description provided.

Table 2

NET BARYON DENSITY D(N)/D(Y) HAS BEEN DETERMINED AT THE RAPIDITY OF NN C.M.S., FOR NET BARYON THE FORMULAR: 2*(P-PBAR)+1.6*(LAMBDA- LAMBDABAR) HAS BEEN USED.

Table 3

No description provided.

Neutral strange particle production in sulphur sulphur and proton sulphur collisions at 200-GeV/nucleon

The NA35 collaboration Bartke, J. ; Bialkowska, H. ; Bock, R. ; et al.

Z.Phys.C 48 (1990) 191-200, 1990.

Inspire Record 304994 DOI 10.17182/hepdata.15177

The production of Λ,$\bar \Lambda$ andKs0 has been studied in 200 GeV/nucleonp+S and S+S collisions in the streamer chamber of the NA35 experiment at the CERN SPS. Significant enhancement of the multiplicities of all observed strange particles relative to negative hadrons was observed in central S+S collisions, as compared top+p andp+S collisions. The latter collisions show no overall (relative) strangeness enhancement overp+p, but the rapidity distributions and hadron multiplicities indicate some secondary cascading production of Λ particles in thep+S andp+Au collisions. The Λ polarization in central S+S collisions was found to be compatible with zero up topT=2 GeV/c.

15 data tables

Table 1

Tranverse kinetic energy spectra of neutral strange particles in P SU collisions.

Table 2

Tranverse kinetic energy spectra of neutral strange particles in P SU collisions.

Table 3

Tranverse kinetic energy spectra of neutral strange particles in SU SU collisions.

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A Study of $K^0_S$, $\Lambda$ and $\bar{\Lambda}$ Production in 60-{GeV} and 200-{GeV} Per Nucleon O Au and $p$ Au Collisions With a Streamer Chamber Detector at the {CERN} {SPS}

The NA35 collaboration Bamberger, A. ; Bartke, J. ; Bialkowska, H. ; et al.

Z.Phys.C 43 (1989) 25, 1989.

Inspire Record 276686 DOI 10.17182/hepdata.15456

The production of neutral strange particlesKso, Λ and$\bar \Lambda $ has been studied in 60 and 200 GeV per nucleon OAu and pAu collisions with the streamer chamber vertex spectrometer of the NA35 experiment at the CERN-SPS accelerator. Ratios of neutral strange particle production to negatively charged particle production in selected regions of phase space were measured to be the same in OAu and pAu reactions. The rates of strange particle production in central OAu collisions are about a factor of 16 higher than in pAu collisions when compared in the same regions of phase space. If an enhancement of strange particle production in OAu collisions relative to pAu collisions is considered to be a signature for quark-gluon plasma formation, no evidence supporting it is observed. The experimental results are compared to the Lund FRITIOF model.

22 data tables

Table 1

No description provided.

Table 2

No description provided.

Table 3

No description provided.