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In this work, we propose a unified model to evaluate processes of electronic interactions of charged particles with hot and dense matter, including energy losses, mean free paths, and thermalization ranges of protons or other light ions. To formulate this method, we introduce modifications to the extended-wave-packet method, which allows one to describe and evaluate the effects of ionization as well as changes in target density and temperature. The ionization of the target leads to the formation of a dense surrounding plasma with distinct energy-absorption properties. We use this unified method to evaluate the contributions of inner shells and free electrons (produced by the target ionization) to the energy loss of protons in Si, C, and Fe targets, on an extensive range of parameters that include low, intermediate, and high energies, with densities and temperatures going from normal laboratory conditions to very high values, such as those of interest for inertial fusion and astrophysical studies. Fil: Archubi, Claudio Darío. Comisión Nacional de Energía Atómica. Centro Atómico Bariloche; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Ciudad Universitaria. Instituto de Astronomía y Física del Espacio. - Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales. Instituto de Astronomía y Física del Espacio; Argentina Fil: Arista, Nestor Ricardo. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Ciudad Universitaria. Instituto de Astronomía y Física del Espacio. - Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales. Instituto de Astronomía y Física del Espacio; Argentina. Comisión Nacional de Energía Atómica. Centro Atómico Bariloche; Argentina

Synopsis We study the vicinage effects in the interaction of H2 + projectiles with C, Al, Si, Al2O3 and SiO2 targets considering the excitation of inner shells. On one side we extend the use of the semiclassical impact-parameter model for the excitation of atomic shells, considering quantum corrections and the role of target screening in the vicinage effects. On the other hand, we adapt our extended wave packet model (EWPM) [3] to the calculation of stopping ratios and ionization cross sections for correlated ions. Lindhard model is used to evaluate valence electrons contributions.

Double differential electron emission distributions produced by grazing impact of fast dressed ions on a Cu(111) surface are investigated focusing on the effects of the electronic band structure. The process is described within the Band-Structure-Based (BSB) approximation, which is a perturbative method that incorporates information of the electronic band structure of the solid. Differences in the behavior of the emission spectra for He+q, Li+q, Be+q and C+q projectiles with different charge states q are explained by the combined effect of the projectile trajectory and the projectile charge distribution.

We present an analytical continuous equation for the Tang and Leschhorn model [Phys. Rev A {\bf 45}, R8309 (1992)] derived from his microscopic rules using a regularization procedure. As well in this approach the nonlinear term $(\nabla h)^2$ arises naturally from the microscopic dynamics even if the continuous equation is not the Kardar-Parisi-Zhang equation [Phys. Rev. Lett. {\bf 56}, 889 (1986)] with quenched noise (QKPZ). Our equation looks like a QKPZ but with multiplicative quenched and thermal noise. The numerical integration of our equation reproduce the scaling exponents of the roughness of this directed percolation depinning model., 8 pages, 4 figures. Submitted to Phys. Rev. E (Rapid Comunication)

We study the electron emission produced by swift protons impinging grazingly on a Beryllium (0001) surface. This material presents a technological interest in modern fusion reactors. We found that surface states play an important role in the double differential energy- and angle- resolved electron emission probabilities, but the effect disappears when angular distributions are integrated to obtain electron energy spectra.