Dr. Navarrete will give two shorter presentations:

*The role of classical uncertainties on the coherence properties of collisions processes*

**Abstract**: The awareness of the relevance of the projectile’s beam coherence effects in ion-atom and ion-molecule collisions has motivated an extensive study on this subject in the recent years. The traditional way to compute the fully differential cross section (FDCS) of a reaction describes the incoming beam of projectiles as a purely coherent quantum system, i.e. a plane-wave. Nevertheless, this assumption seems not justified enough when we look at this postulate under the light of the density matrix theory. We will describe how the time propagation of an incoherent mixture of an ensemble of massive particles, described by identical wave packets located at different positions upon a much larger region of dimension D, can eventually develop coherence at a given distance L, and its implications for scattering theory. Furthermore we will show results of this concepts applied to specific experimental results.

*Multi-channel contributions to High Harmonic Generation in solids*

**Abstract**: Unlike High-harmonic generation in solids (HHG) from gaseous atoms for which there is a great consensus and vast knowledge of its characteristics, the main features of HHG in solids are still under discussion, which has been fueled by its recent experimental discovery. We will show a detailed analysis of the intra- and interband dynamics by an adiabatic basis-set approach within the whole BZ and how they can be easily understood by means of a simple model which allows for analytical approximations of the contributions of each separate crystal momentum channel. Furthermore, we also compare the HHG spectra for a two-band calculation and the features which emerge in a many-band calculation when we consider the integration of the spectra over the entire BZ with contributions from the band center (Γ point) alone.

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