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Measurements of light nuclei production in 11.5-A-GeV/c Au + Pb heavy-ion collisions.

The E864 collaboration Armstrong, T.A. ; Barish, K.N. ; Batsouli, S. ; et al.

Phys.Rev.C 61 (2000) 064908, 2000.

Inspire Record 525664 DOI 10.17182/hepdata.25465

We report on measurements by the E864 experiment at the BNL-AGS of the yields of light nuclei in collisions of Au(197) with beam momentum of 11.5 A GeV/c on targets of Pb(208) and Pt(197). The yields are reported for nuclei with baryon number A=1 up to A=7, and typically cover a rapidity range from y(cm) to y(cm)+1 and a transverse momentum range of approximately 0.1 < p(T)/A < 0.5 GeV/c. We calculate coalescence scale factors B(A) from which we extract model dependent source dimensions and collective flow velocities. We also examine the dependences of the yields on baryon number, spin, and isospin of the produced nuclei.

14 data tables

Table 1

10 pct most central collisions.

Table 2

10 to 38 pct most central collisions.

Table 3

38 to 66 pct most central collisions.

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Measurements of neutrons in 11.5-A-GeV/c Au + Pb heavy-ion collisions.

The E864 collaboration Armstrong, T.A. ; Barish, K.N. ; Batsouli, S. ; et al.

Phys.Rev.C 60 (1999) 064903, 1999.

Inspire Record 506495 DOI 10.17182/hepdata.31358

We present measurements from Brookhaven Experiment 864 of neutron invariant multiplicity in 11.5 A GeV/c Au+Pb collisions. The measurements span a rapidity range from center-of-mass to beam rapidity (y(beam)=3.2) and are presented as a function of event centrality. The results are compared with E864 measurements of proton invariant multiplicity and an average n/p ratio at hadronic freeze-out of 1.19+-.08 is determined for the rapidity range y=1.6 to y=2.4. We discuss briefly the implications of this ratio within a simple equilibrium model of the collision system.

1 data table

Table 1

The errors are statistical and systematic errors added in quadrature. 10% most central events.

Antiproton production and antideuteron production limits in relativistic heavy ion collisions from BNL experiment 864.

The E864 collaboration Armstrong, T.A. ; Barish, K.N. ; Batsoulli, S. ; et al.

Phys.Rev.C 59 (1999) 2699-2712, 1999.

Inspire Record 478873 DOI 10.17182/hepdata.31371

We present results from Experiment 864 for antiproton production and antideuteron limits in Au + Pb collisions at 11.5 GeV/c per nucleon. We have measured invariant multiplicities for antiprotons for rapidities 1.4<y<2.4 at low transverse momentum as a function of collision geometry. When compared with the results from Experiment 878 our measurements suggest a significant contribution to the measured antiproton yield from the decay of strange antibaryons. We have also searched for antideuterons and see no statistically significant signal. Thus, we set upper limits on the production at approximately 3 x 10^{-7} per 10% highest multiplicity Au + Pb interaction.

7 data tables

Table 1

CENTRALITY = 10 PCT.

Table 2

CENTRALITY = 100 TO 70 PCT.

Table 3

CENTRALITY = 70 TO 30 PCT.

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Xi and Antixi production in 158-GeV/nucleon Pb + Pb collisions.

The NA49 collaboration Appelshäuser, H. ; Bächler, J. ; Bailey, S.J. ; et al.

Phys.Lett.B 444 (1998) 523-530, 1998.

Inspire Record 477539 DOI 10.17182/hepdata.31330

We report measurements of Xi and Xi-bar hyperon absolute yields as a function of rapidity in 158 GeV/c Pb+Pb collisions. At midrapidity, dN/dy = 2.29 +/- 0.12 for Xi, and 0.52 +/- 0.05 for Xi-bar, leading to the ratio of Xi-bar/Xi = 0.23 +/- 0.03. Inverse slope parameters fitted to the measured transverse mass spectra are of the order of 300 MeV near mid-rapidity. The estimated total yield of Xi particles in Pb+Pb central interactions amounts to 7.4 +/- 1.0 per collision. Comparison to Xi production in properly scaled p+p reactions at the same energy reveals a dramatic enhancement (about one order of magnitude) of Xi production in Pb+Pb central collisions over elementary hadron interactions.

2 data tables

Table 1

Data are given at the midrapidity value.

Table 2

Requested data from authors.

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

Table 1

No description provided.