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The effect of the deposition of kinetic energy and neutralization energy of slow highly charged xenon ions on the process of the nanostructures creation at the surface of gold nanolayers is investigated. The nanolayers of thickness of 100 nm were prepared by e-beam evaporation of gold on crystalline silicon Si(100) substrate. The samples were irradiated at the Kielce EBIS facility of the Jan Kochanowski University (Kielce, Poland), under high vacuum conditions. The irradiations were performed for constant kinetic energy 280 keV and different ions charge states (Xe$^{q+}$, q = 25, 30, 35, 36 and 40) and for constant charge state Xe$^{35+}$ and different kinetic energies: 280 keV, 360 keV, 420 keV and 480 keV. The fluence of the ions was on the level of 10$^{10}$ ions/cm$^2$. Before and after irradiation the nanolayer surfaces were investigated using the atomic force microscope. As the result, well pronounced modifications of the nanolayer surfaces in the form of craters have been observed. A systematic analysis of the crater sizes (diameter on the surface and depth) allowed us to determine the influence of the deposited kinetic and the neutralization energy on the size of the obtained nanostructures. The results are theoretically interpreted within the micro-staircase model based on the quantum two-state vector model of the ionic Rydberg states population. The charge dependent ion-atom interaction potential inside the solid is used for the calculation of the nuclear stopping power. According to the model the formation of the nanostructures is governed by the processes of the ionic neutralization in front of the surface and the kinetic energy loss inside the solid., Comment: 12 pages, 7 figures, Submitted to Vacuum journal on May 29th, 2022

Synopsis In this work we have systematically studied process of energy deposition and formation of nanostructures on metallic (Au nanolayer) surfaces as a result of the irradiation with slow highly charged xenon ions (HCI). Well pronounced modifications of the surfaces in form of craters were observed. We found that, in the systems considered, the kinetic energy influences the crater depth, while the potential energy affects the crater size at the surface. This finding showed that for gold nanolayers the potential energy plays important role in the nanostructures creation.

In Poland the intention is to use RODOS as the software framework for the Integrated Emergency Data Management and Decision Support System (EDMDSS), whose structure will account for the existence of specialised centres, with responsibilities relating to meteorological fields diagnoses and predictions, measured radiological data collection and examining the feasibility of countermeasures to work out rational decisions. The system will be distributed and functionally integrated in order to take best advantage of current organisational arrangements in Poland. A parallel workstation platform and dedicated package will be used for downscaling coarse data from national meteorological and special emergency mode operation for weather predictions.

The variational formulation for stiff boundary value and eigenvalue problem is considered. The asymptotics of solutions to such problems is found. The theory is applied to the neutron transport problem.

The weak solution problem for the neutron transport equation is formulated in terms of appropriate bilinear forms. Then the theory of approximate methods for solving the problem is presented.

The stiff boundary value problem for the time-independent linear Boltzmann equation is considered in the variational formulation in terms of the coercive symmetric bilinear form. It is shown that it is asymptotically equivalent to the related variational diffusion problem when the stiffness parameter tends to zero. Higher order perturbations are also discussed.

The critical problem for a finite reactor system is formulated in the framework of the multigroup approximation. Under the condition that the system has spectrum-regenerated properties it is proved that the critical problem to the multigroup transport equation has a unique solution. This solution is nonnegative and essentially bounded everywhere.

One of the most important problems in neutron thermalization theory is the time behavior of neutron pulse in a finite sample of moderating medium. In the last few years a great number of papers have been published on this subject (see, e.g., [l-4]). However, the present status of the theory is far from being satisfactory since most of the authors are forced to make several restrictive assumptions concerning either the space-dependence of the neutron distribution or the scattering kernel. In particular, most of the results obtained so far are valid only for the isotropic scattering. In this paper we try to prove some properties of the realistic nonisotropic scattering kernels in various types of moderators which have direct consequences in the time-dependent thermalization. The analysis will be based upon the Van Hove theory of thermal neutron scattering. The transport equation describing the behavior of neutrons in a sourcefree, uniform, nonmultiplying medium has the following form