[en] One can study the expansion phase in the TDHF (Time Dependent Hartree Fock) approximation. The scenario sketched above is based on nuclear matter ideas. In practice the compressed zone is finite and the surface will play a role. We will subject ¹⁶O and ⁸⁰Zr to various initial compressions and subsequently follow the time evolution in the TDHF approximation. (orig./HSI)

[en] It was the aim of this compilation of possible particle production experiments at SIS energies to show the potential progress which arises from large improvements in beam intensity and quality. (orig./HSI)

[en] Electromagnetic dissociation of ⁵⁹Co, ⁸⁹Y, and ¹⁹⁷Au target nuclei by the Coulomb field of relativistic heavy ions (RHI) was inferred from measurement of one-neutron removal cross sections. The projectiles ranged from 2.1-GeV protons to 1.7-GeV/nucleon ⁵⁶Fe. In most cases the experimental cross sections in excess of the estimated nuclear contributions are well described by use of the Weizsaecker-Williams method for calculating the electromagnetic dissociation contributions. (orig.)

[en] Japanese American Cooperative Emulsion Experiment (JACEE) has been measuring ultrarelativistic comic ray nucleus and sampling the events in the energy regions both 10 to 100 GeV/A and above TeV/A by balloon emulsion chamber since 1979. In this report main results obtained up to now will be described. (orig./HSI)

[en] The cross sections for break-up of ²³⁸U in targets ranging from H to Pb are presented. Fragmentation modes measured include: total charge changing, fission, and central collision. The charge changing cross sections are compared with black disk geometrical and Glauber models. The central collision cross section rises as the mass of the target and reaches 20% of the measured cross section for uranium on a lead target. The limiting fragmentation hypothesis is satisfied for targets heavier than hydrogen. For uranium-uranium central collisions this data predicts a cross section of 2.5 barns. (orig.)

[en] We discuss strange particle production in nucleus nucleus collisions at incident energies per nucleon of 2 to 4 GeV. In our comparison with the experimental data we concentrate on cascade model calculations. It is shown that the various cascade models all yield qualitatively similar results. The large K⁺ transverse momenta observed cannot be explained. Whether this is due to a genuine physical effect not yet understood or merely a consequence of the oversimplified treatment of the scattering of the produced K⁺ on the surrounding baryonic medium, remains at present an open question. For K^- production, as well as for Λ production at Dubna energies, the agreement with the experimental data is in general better. We point out the necessity for future experimental and theoretical efforts to clarify the picture of strange particle production. (orig.)

[en] The phase space of channels is calculated into which a nucleus may decay after being hit by a proton with Esub(p) > 10 GeV. Special care is given to the finite size of the system and to the Couloub interaction between the fragments. Both effects are shown to be of crucial and dominant importance. At a temperature of 4-5 MeV the target decays into many fragments simultaneously. The mass yields is reproduced by the model over the entire mass range. Monte Carlo simulations show that also the energy spectra may realistically be reproduced and the slope parameter (the apparent temperature) Tsub(app) is proportional2 times larger than the true temperature. This is due to considerable fluctuations in the number of fragments and in their mutual Coulomb-interaction. The gas-liquid phase transition in nuclear matter is dramatically modified by these finite size and strong Coulomb effects. Some general features of this transition are discussed. (orig.)

[en] A stack of Br-2 electron sensitive emulsions (10 x 20 x 0.06 cm each) was exposed to the 4.5 Gev/A*c ¹²C-beam of the JINR synchrophasotron at Dubna. The beam fluence was 2.5*10⁴/cm²; the minimum grain density was 19/100 um. The primary carbon nuclei were scanned along the track under 45x objectives until they interacted or up to a maximum distance D₀ = 5 cm; event analysis was done with 100x immersion objectives. Interactions were defined by the emission of at least one hadronic track. The secondaries were identified by measurement of mean gap-length for 2 <= Z <= 3, and of delta-ray density for Z = 4-6. (orig./HSI)

[en] Pion and proton emission are used to investigate thermal equilibrium in central collisions of ⁴⁰Ar + KCl at 1.8 GeV/nucleon. The bulk of the yield is isotropic in the c.m. system, the protons have an apparent temperature of 118 MeV while the pions have a much lower temperature of 58 MeV. It is shown that the discrepancy of temperatures can be explained by the decay kinematics of delta resonances in thermal equilibrium as well as by collective radial flow in the expansion stage of the interaction. (orig.)

[en] Preliminary analysis of pion production in 1.2 GeV/nucleon Kr-RbBr collisions is presented. The negative pion multiplicity is consistent with a convolution of Poisson distributions and a freeze-out density between 1/3 and 1/2 normal nuclear density is extracted. Global negative pion kinematic variables are used to search for possible structure in the multi-pion emission. No evidence for structured emission or conservation constraints is found. Pion interferometry analysis gives a source radius of 5.4 +- 1.2 Fermi and a freeze-out density of .3 +- .2 times normal nuclear density. (orig.)