D. Best

Central collisions of Au on Au at 150, 250 and 400 A·MeV

Abstract Collisions of Au on Au at incident energies of 150, 250 and 400 A ·MeV were studied with the FOPI-facility at GSI Darmstadt. Nuclear charge ( Z ⩽ 15) and velocity of the products were detected with full azimuthal acceptance at laboratory angles 1° ⩽ θ lab ⩽ 30°. Isotope separated light charged particles were measured with movable multiple telescopes in an angular range of 6–90°. Central collisions representing about 1% of the reaction cross section were selected by requiring high total transverse energy, but vanishing side flow. The velocity space distributions and yields of the emitted fragments are reported. the data are analysed in terms of a thermal model including radial flow. A comparison with predictions of the quantum molecular model is presented.

On the transverse momentum distribution of strange hadrons produced in relativistic heavy ion collisions

Particles with strange quark content produced in the system 1.93A·GeV58Ni on58Ni have been investigated at GSI Darmstadt with the FOPI detector system. The correlation of these produced particles was analyzed with respect to the reaction plane.Λ baryons exhibit a very pronounced sideward flow pattern which is qualitatively similar to the proton flow. However, the kaon (K+,Ks0) flow patterns are significantly different from that of the protons, and their form may be useful to restrict theoretical models on the form of the kaon potential in the nuclear medium.

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

Abstract 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 58Ni with 58Ni nuclei. The transverse mass (mt) spectra have been studied as a function of rapidity at a beam energy 1.93 AGeV. The mt 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 A GeV, 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.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

Identification of baryon resonances in central heavy-ion collisions at energies between 1 and 2 AGeV

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Abundance of Δ resonances in 58Ni + 58Ni collisions between 1 and 2 AGeV

Ni with

Out-of-plane emission of nuclear matter in Au+Au collisions between 100 and 800 AMeV

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Onset of nuclear matter expansion in Au+Au collisions

Ni nuclei. The transverse mass (

Flow angle from intermediate mass fragment measurements

m_t

Azimuthal anisotropies as stringent test for nuclear transport models

) spectra have been studied as a function of rapidity at a beam energy 1.93 AGeV. The

Charged pion production in Au on Au collisions at 1 AGeV The FOPI Collaboration

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