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 sideflow. 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.PACS: 25.70.Pq

Double differential cross sections have been measured for energetic p, d, t, and u particles emitted in reactions of 315 MeV "0 ions on '"U, In coincidence with light-particle emission, the momentum transfer to the target is determined by measuring the folding angle between the two fission fragments resulting from the sequential decay of the target nucleus. It is concluded that the emission of these particles occurs predominantly in fusionlike "central" collisions and at an early stage of the reaction. The energy and angular distributions are described by thermal emission from a source moving with approximately half of the beam velocity. Alternatively, the energy spectra can be explained by emission from a rotating hot spot. The cross sections for d, t, and a emission can be described in terms of a generalized form of the coalescence model which takes into account the Coulomb repulsion from the target nucleus.NUCLEAR REACTIONS U( O, Xf), x=p, d, t, e, E=315 MeV;measured z(E, 8") and fission fragment folding angle distribution. Analysis in terms of hot spot, moving source, and coalescence models.

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Double differential cross sections have been measured for energetic p, d, t, and u particles emitted in 0-induced reactions on targets of Al, Zr, and Au at incident energies of 140, 215, and 310 MeV. The energy and angular distributions are well described by isotropic emission from a moving thermal source. The extracted temperature and velocity parameters are found to vary systematically with the incident energy per nucleon above the Coulomb barrier. The observed trends cannot be explained by compound nucleus emission but instead suggest emission from a source which consists of comparable contributions from target and projectile. Alternatively, the proton energy spectra are compared with a precompound model and with a simple knockout model. The d, t, and a-particle cross sections are also described in terms of a generalized coalescence relation which takes into account Coulomb repulsion from the target nucleus. NUCLEAR REACTIONSAl(' O~), E=140, 215, and 310 MeV; Zr(' O~), E =215 and 310 MeV; ' Au('6O~), E =140, 215, and 310 MeV; x =p, d, t, and a. Measured o. (E",O"}. Analysis in terms of moving source, precompound, knockout, and coalescence models.

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Abstract. The goal of the FAZIA Collaboration is the design of a new-generation 4π detector array for heavy-ion collisions with radioactive beams. This article summarizes the main results of the R&D phase, devoted to the search for significant improvements of the techniques for charge and mass identification of reaction products. This was obtained by means of a systematic study of the basic detection module, consisting of two transmission-mounted silicon detectors followed by a CsI(Tl) scintillator. Significant improvements in ΔE-E and pulse-shape techniques were obtained by controlling the doping homogeneity and the cutting angles of silicon and by putting severe constraints on thickness uniformity. Purposely designed digital electronics contributed to identification quality. The issue of possible degradation related to radiation damage of silicon was also addressed. The experimental activity was accompanied by studies on the physics governing signal evolution in silicon. The good identification quality obtained with the prototypes during the R&D phase, allowed us to investigate also some aspects of isospin physics, namely isospin transport and odd-even staggering. Now, after the conclusion of the R&D period, the FAZIA Collaboration has entered the demonstrator phase, with the aim of verifying the applicability of the devised solutions for the realization of a larger-scale experimental set-up.

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