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This contribution reports on the cross section measurements performed at GSI on the isotopic distribution of the residual nuclides of spallation reactions in inverse kinematics. The fragment separator (FRS) was used to select and identify the reaction products, and the full (Z,N) map was measured above the production limit of 0.1 mb. The high resolution of the spectrometer allowed to determine the velocity distributions of all products. These data are relevant for the design of accelerator-driven subcritical reactors. They are also of the highest importance to improve the understanding of the spallation mechanism.

If simplified, every information retrieval problem can be solved when the information need implied by its expression has been identified. We are interested in the criteria used in realising a good information retrieval problem expression. We have listed these criteria through some principles and maxims which first characterized the communication between two persons are applied. We choose to use the gricean maxims because they are the most favoured for this type of situation. Secondly, we have tried to identify some others principles that can be used to realise a good information retrieval problem expression. The principles by Grice can not resolve all forms of error associated with this particular form of communication. In our work, we defined three other principles namely: adhesion principle, reformulation principle, memorization principle. We give some examples of situations where the principles we have formulated are not applicable and the consequences. We present the possible applications of our new model: MIRABEL, which can help in the description of information retrieval problem from. It also compels its user to use essential good expression principle implicitly.

Calculations which describe the probability to break a pair on the way from saddle to scission point when the nucleus undergoes fission are presented. It is shown that they reproduce the main characteristics of the measured data on even-odd structure in fission-fragment yields. In particular, the strongly differing even-odd structures in proton and neutron numbers are explained within the assumption of thermal equilibrium of intrinsic excitations at scission.

The microscopic structure of the Gamow-Teller resonance (GTR) and spin-dipole resonance (SDR) in 208Bi has been investigated in the 208Pb(3He,tp)207Pb reaction at E(3He)=450 MeV and very forward scattering angles. The partial and total branching ratios and the escape widths for GTR and SDR decay to the residual neutron-hole states in 207Pb were deduced. These are found to be in good agreement with recent theoretical estimates. The (3He,tp) reaction on Pb at E(3He)=177 MeV was also studied in order to locate isovector monopole strength corresponding to 2ℏω transitions. Monopole strength at excitation energies above 25 MeV was discovered and compared to calculated strength due to the isovector giant monopole resonance and the spin-flip isovector monopole resonance. Calculations in a normal-mode framework show that all isovector monopole strength can be accounted for if the branching ratio for decay by proton emission is 20%.