[en] Using first order calculations derived for an achromatic system A) (delta xsub(F)/delta Esub(i) = 0) or an optimised system 0) (xsub(F) minima), it is shown that the final resolution measured in the focal plane (possibly kinematically displaced) of the spectrometer, depends only on the emittance of the accelerator and of the efficient area of the analyser, exclusive of the properties of the spectrometer. The use of this result is only limited by higher order terms in the calculation, or by considerations out of the scope of this article, like target effects etc..

[en] The last results obtained in the study of the transfer mechanism in the reaction ¹⁶O(¹⁶O,¹²C)²⁰Ne are given. The polarization of the residual nucleus has been measured versus the ¹²C angle. Significant differences observed in the comparison of the experimental results to the prediction of different models lead to the conclusion that some part of the mechanism, specific to the interaction between heavy ions, needs to be introduced

[en] The elastic scattering angular distributions of ¹⁶O at 94 MeV/u on ¹²C, ²⁸Si, ⁴⁰Ca, ⁹⁰Zr, ²⁰⁸Pb targets have been measured. They have been analyzed in the framework of the optical model with Woods-Saxon potentials and in the framework of the folding model. Concerning the heaviest system ¹⁶O + ²⁰⁸Pb, these analyses show that the real potential is well-defined only in the vicinity of the strong absorption radius, whereas for the lighter systems, it is defined in a relatively wide region (2-3 fm), which corresponds to a strong overlap of the two nuclei, especially for the systems ¹⁶O + ²⁸Si and ¹⁶O + ¹²C. This difference, between the ¹⁶O + ²⁰⁸Pb system and the other systems originates in the appearance of the far-side contribution which manifests itself in the angular distributions by the so-called Fraunhoefer oscillations. The imaginary part of the potential is determined only in the vicinity of the strong absorption radius. The large reduction of the strong absorption radius for all the studied systems as the energy increases shows that the nuclear surface transparency is strongly enhanced at intermediate energies. The calculations performed with folding potentials allowed a study of the nuclear potential strength, in a less ambiguous way than with phenomenological potentials. In the regions where they are well-defined, the real and imaginary potentials decrease regularly when the energy goes from 10 to 100 MeV/u. This decrease disagrees with the results of microscopic calculations which predict an increase or a saturation of the nuclear potential in this energy range

[en] Having recalled the 1935 debate between A. Einstein and N. Bohr about quantum mechanics (Q.M.) the thought-experiment of D. Bohm is described and a new derivation of the Bell's inequalities is established to test the class of theories based on the hypothesis of hidden-parameters in the common past. It is shown that Q.M. violates these inequalities almost everywhere. The general properties of functions satisfying Bell's inequalities are studied in order to compare them to Q.M. predictions as regards derivatives, integrals, values, intervals, amplitudes and finally the overall behaviour: a few of the Bell's functions chosen to approach somehow Q.M. are given. Altogether, in the comparison between Q.M. and functions satisfying Bell's inequalities, an incompatibility is revealed that is stronger then that resulting from consideration of just the inequalities

[en] Two heavy-ion experiments are reported which both use a magnetic spectrometer. The equipment of the focal plane of the magnet is based on the use of a set of gaz counters which are described. A method for the reconstitution of trajectories is given. The aim of the experiments is to reach a deeper knowledge of the reaction mechanism in the case of a heavy ion induced α transfer reaction. Correlation experiments are performed in order to measure the polarization of the residual nucleus. The other experiment is done in order to measure the mass excess of some light exotic nuclei and the excitation energy of their first excited state by relative Q-value measurements

[en] In the disintegration of halo nuclei, two fundamental constraints appear in the transverse and longitudinal impulse distribution analysis of disintegration products. These constraints result from Heisenberg's uncertainty principle applied to the observed values of transverse momentum only, and to both transverse and parallel momentum values. These constraints are: 1 - the observed transverse impulse values are of the same order of amplitude (a few tenth of MeV/c) than those only resulting from the radial dimension constraint in the collision. For every fragment emitted during the collision, the whole radial emission surface must be taken into account. 2 -The final state interaction of the disintegration products is an essential element of the reaction mechanism. These constraints are illustrated by examples of heavy ion reactions. (J.S.). 3 refs., 4 figs

[en] Using first order calculations derived for an achromatic system A) (deltaxsub(F)/deltaEsub(i)=0) or an optimised system O) (xsub(F) minima). It is shown that the final resolution measured in the local plane of the spectrometer depends only on the emittance of the accelerator and of the efficient area of the analyser exclusive of the properties of the spectrometer. The use of this result is only limited by higher order terms in the calculation or considerations out of this scope like target effects etc..

[en] A detailed comparison of Bell's inequalities (B.I.) and quantum mechanics (Q.M.) in an E.P.R.B. situation is given. It is first shown that Q.M. violates the original (3 directions) or generalized (4 directions) B.I. almost everywhere. The properties of functions satisfying the original B.I. are then derived and compared to Q.M. predictions. Finally, the behaviour of functions which satisfy B.I. and attempt to fit Q.M. is described. Altogether, an incompatibility is shown to be stronger than that resulting from just the usual examination

[en] An original method based on the use of a double magnetic spectrometer in a telescopic mode is proposed for the studies of heavy ions collisions both at very forward angles and for magnetic rigidities close to that of the beam. It consists in the direct measurement of angular distributions on doubly - Bρ and angle - sorted events. The method has been tested on the LISE spectrometer at GANIL with a 44 MeV/A ⁴⁰ Ar beam impinging on C, Al, Ni and Au targets. Milliradian angular accuracy have been obtained at magnetic rigidities as close as 0.9977 of that of the beam

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