[en] Short communication. 7 refs

[en] A phenomenological and analytical formula for nuclear level densities is proposed, that reproduces microscopic Nilsson-BCS calculations, with inclusion of the blocking effect for odd N and/or Z nuclei. A simple energy dependence of the level density parameter a is obtained in the interval ranging from 4 to 20 MeV for a number of nuclei in the mass region 124 less than or equal to A less than or equal to 160. 14 references

[en] The contribution of collective degrees of freedom to nuclear level density has been evaluated within the framework of the Interacting Boson Model. The enhancement factor due to collective excitations has been calculated for transitional nuclei in the mass ranges A = 150 and A = 190

[en] The parity distribution of nuclear excited states is investigated in the frame of a statistical microscopic Nilsson-BCS formalism. Calculations performed for medium-mass nuclei (51 <= A <= 66) show that the parity equiprobability holds at excitation energies greater than 15 MeV, in agreement with the experimental information. (author)

[en] Short communication. 5 refs

[en] When the thermal diffusivity, χ, of a thin film on a substrate is measured by means of the mirage method, the photothermal deflection of the probe beam is determined by the heat radiation field contributed by the film and the substrate, heated by the pump beam. A two-dimensional algorithm is here presented in order to deduce the measure of the diffusivities of the film and the substrate in one set of mirage detection from the experimental data

[en] A simple algebraic model of superheavy and superdeformed nuclei, produced through heavy-ion collisions is presented, based on a microscopic evaluation of the effective boson numbers in the actinide and superheavy regions. The relevant calculations have been performed within the framework of a deformed shell model, including the pairing interaction between like-particles. As far as the actinide isotopes are concerned, the theoretical boson numbers are compared with the corresponding empirical estimates, obtaining a good agreement. The calculated boson numbers are used to predict collective spectra and electromagnetic transition intensities for actinide - including fission isomers - and superheavy nuclei, by using the interacting boson model (IBM). (author)

[en] We present main results of molecular dynamics simulations that we have carried out in order to investigate structural properties of polyamidoamine (PAMAM) dendrimers. Obtained data confirm the PAMAM dendrimer structure proposed by experiments, performed by means of X-ray scattering (SAXS) and quasi-elastic light scattering (QELS) techniques

[en] Main aspects are discussed concerning nuclear reaction cross-sections for PIXE and PIGE (Particle Induced Gamma-ray Emission) analyses, especially referring to cultural heritage diagnostics, within the framework of ion beam analysis (IBA) methods, also reviewing recent results from international Conferences on Nuclear Data for Science and Technology and from NEANSC meetings and IAEA initiatives on the matter.To sum up this work, it is then worth remarking the following items: IBA techniques are powerful tools to derive unique information as for corrosion, degradation and, generally, conservation conditions of materials. Careful analyses of specific systems require accurate evaluations and establishment of complete databases, in particular for stopping powers and relevant cross sections. The physical parameters to be accurately determined are, therefore, nuclear reaction cross sections of importance for NRA analysis of light elements and stopping powers and ranges of light and heavy ions in various matrices. Light elements (H, Li, B, C, N, O, etc.) play an important role as constituents of many important organic as well inorganic materials in historical and artistic objects. To a large extent these materials occur in the near-surface area of a material with altered or degraded composition

[en] The matter is reviewed, also following previous discussions at ICRS-9, concerning evaluation and related theoretical activities on nuclear data for radiation shielding within the framework of international co-operation initiatives, according to recognised needs and priorities. Both cross-section data.- for reactions induced by neutrons and photons - and nuclear structure data have been considered. In this context, main contributions and typical results are presented from theoretical and evaluation activities at the ENEA Applied Physics Division, especially concerning neutron induced reaction data up to 20 MeV and photonuclear reaction data such as photon absorption and (gamma,n) cross-sections. Relevant aspects of algebraic nuclear models and of evaporation and pre-equilibrium models are discussed. (authors)