Recent results from NA44 and a review of HBT

The NA44 collaboration Jacak, B.V. ; Boggild, H. ; Boissevain, J. ; et al.
Nucl.Phys.A 590 (1995) 215C-232C, 1995.
Inspire Record 407654 DOI 10.17182/hepdata.36517

None

1 data table

PRELIMINARY DATA FOR CENTRAL EVENTS.


Charged hadron distributions in p A and A-A collisions at the CERN SPS

The NA44 collaboration Dodd, Jeremy ; Bøggild, H. ; Boissevain, J. ; et al.
Nucl.Phys.A 590 (1995) 523C-526C, 1995.
Inspire Record 407678 DOI 10.17182/hepdata.36504

Single particle distributions of π ± , K ± , p , p and d near mid-rapidity from 450 GeV/c p A and 200 GeV/c per nucleon SA collisions are presented. Inverse slope parameters are extracted from the transverse mass spectra, and examined for indications of collective phenomena. Proton and antiproton yields are determined for different projectile-target combinations. First results from 160 GeV/c per nucleon PbPb collisions are presented.

2 data tables

No description provided.

PRELIMINARY DATA FOR CENTRAL EVENTS.


Hadron distributions: Recent results from the CERN experiment NA44

The NA44 collaboration Xu, Nu ; Bearden, I.G. ; Bøggild, H. ; et al.
Nucl.Phys.A 610 (1996) 175C-187C, 1996.
Inspire Record 432743 DOI 10.17182/hepdata.36469

Proton distributions at midrapidity have been measured for 158A·GeV Pb+Pb collisions in the focusing spectrometer experiment NA44 at CERN. A high degree of nuclear stopping is found in the truly heavy ion collisions. Systematic results of single particle transverse momentum distributions of pions, kaons, and protons, of 200A·GeV S+S and 158A·GeV Pb+Pb central collisions will be addressed within the context of thermalization. By comparing these data with thermal and transport models, freeze-out parameters such as the temperature parameter T fo and mean collective flow velocity 〈β〉 are extracted. Preliminary results of the particle ratios of K − K + and p p are discussed in the context of cascade models of RQMD and VENUS.

1 data table

CENTRAL COLLISIONS: SIG(TRIG)/SIG(GEOM)=10%.


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

Data obtained from the fit of MT spectra.

Data obtained from the fit of MT spectra.


Strange meson enhancement in Pb Pb collisions.

The NA44 collaboration Bearden, I. ; Bøggild, H. ; Boissevain, J. ; et al.
Phys.Lett.B 471 (1999) 6-12, 1999.
Inspire Record 504074 DOI 10.17182/hepdata.31360

The NA44 Collaboration has measured yields and differential distributions of K+, K-, pi+, pi- in transverse kinetic energy and rapidity, around the center-of-mass rapidity in 158 A GeV/c Pb+Pb collisions at the CERN SPS. A considerable enhancement of K+ production per pi is observed, as compared to p+p collisions at this energy. To illustrate the importance of secondary hadron rescattering as an enhancement mechanism, we compare strangeness production at the SPS and AGS with predictions of the transport model RQMD.

4 data tables

Inverse slope paramters of the (1/MT)*DN/DMT distribution.

Rapidity distributions for K+ and K- production.. Statistical and systematic errors added in quadrature.

Rapidity distributions for PI+ and PI- production.. Statistical and systematic errors added in quadrature.

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Production of charged kaons in central S + S and O + Au collisions at 200-GeV/nucleon

The NA35 collaboration Kowalski, M. ; Bachler, J. ; Bartke, J. ; et al.
Nucl.Phys.A 544 (1992) 609C-614C, 1992.
Inspire Record 343256 DOI 10.17182/hepdata.36667

Product of charged kaons in central S + S and O + Au collisions at 200 GeV/nucleon has been studied in the NA 35 Streamer Chamber experiment. Mean multiplicities and transverse mass distributions were obtained. They were compared with nucleon-nucleon data and with model predictions.

5 data tables

No description provided.

No description provided.

No description provided.

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Recent results from experiment NA35.

The NA35 collaboration Seyboth, P. ; Baechler, J. ; Bartke, J. ; et al.
Nucl.Phys.A 544 (1992) 293C-307C, 1992.
Inspire Record 343637 DOI 10.17182/hepdata.36668

Enhanced strange particle production, nonstatistical multiplicity fluctuations and two-pion Bose-Einstein correlations were measured in O, S-nucleus reactions at 60 and 200 GeV/nucleon. The results indicate significant collective effects in high-energy nucleus-nucleus collisions.

2 data tables

CENTRAL COLLISIONS.

CENTRAL COLLISIONS.


Production of charged kaons in proton - nucleus and nucleus-nucleus collisions at 200-GeV/Nucleon

The NA35 collaboration Baechler, J. ; Bartke, J. ; Białkowska, H. ; et al.
Z.Phys.C 58 (1993) 367-374, 1993.
Inspire Record 342660 DOI 10.17182/hepdata.14428

Production of charged kaons in proton-sulphur, proton-gold, sulphur-sulphur and oxygen-gold collisions at 200 GeV/nucleon has been studied in the NA35 Streamer Chamber experiment. Rapidity and transverse mass distributions as well as mean multiplicities were obtained. The results are compared with nucleon-nucleon data and with model predictions.

22 data tables

Tranverse mass distribution for all charged kaons in S S collisions for the limited yrap range 1.4 to 2.4.

Tranverse mass distribution for K0S production in the limited rapidity range 1.4 to 2.4. Data are taken from Bartke et al. ZP C48 (1990) 191.

Rapidity distribution for K+ production in p SU interactions.

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Collective expansion in high energy heavy ion collisions.

The NA44 collaboration Bearden, I.G. ; Boggild, H. ; Boissevain, J. ; et al.
Phys.Rev.Lett. 78 (1997) 2080-2083, 1997.
Inspire Record 426801 DOI 10.17182/hepdata.52345

Transverse mass spectra of pions, kaons, and protons from the symmetric heavy-ion collisions 200 A GeV S+S and 158 A GeV Pb+Pb, measured in the NA44 focusing spectrometer at CERN, are presented. The mass dependence of the slope parameters provides evidence of collective transverse flow from expansion of the system in heavy-ion induced central collisions.

3 data tables

(1/MT)*d(N)/d(MT) = A *exp(-MT/SLOPE).

(1/MT)*d(N)/d(MT) = A *exp(-MT/SLOPE).

The SLOPE from the parameterization of (1/MT)*d(N)/d(MT) = A*exp(-MT/SLOPE)is fitted as follows SLOPE = CONST(C=1) + M(hadron)*CONST(C=2)**2.


K+ production in the reaction Ni-58 + Ni-58 at incident energies from 1-A-GeV to 2-A-GeV.

The FOPI collaboration Best, D ; Herrmann, N ; Hong, B ; et al.
Nucl.Phys.A 625 (1997) 307-324, 1997.
Inspire Record 441884 DOI 10.17182/hepdata.36288

Semi-inclusive triple differential multiplicity distributions of positively charged kaons have been measured over a wide range in rapidity and transverse mass for central collisions of $^{58}$Ni with $^{58}$Ni nuclei. The transverse mass ($m_t$) spectra have been studied as a function of rapidity at a beam energy 1.93 AGeV. The $m_t$ distributions of K^+ mesons are well described by a single Boltzmann-type function. The spectral slopes are similar to that of the protons indicating that rescattering plays a significant role in the propagation of the kaon. Multiplicity densities have been obtained as a function of rapidity by extrapolating the Boltzmann-type fits to the measured distributions over the remaining phase space. The total K^+ meson yield has been determined at beam energies of 1.06, 1.45, and 1.93 AGeV, and is presented in comparison to existing data. The low total yield indicates that the K^+ meson can not be explained within a hadro-chemical equilibrium scenario, therefore indicating that the yield does remain sensitive to effects related to its production processes such as the equation of state of nuclear matter and/or modifications to the K^+ dispersion relation.

1 data table

No description provided.