Barred galaxies in cosmological simulations. Tidal perturbations and feedback.

Bars are truly common objects among disc galaxies. Even though it is now commonly accepted that non-axisymmetric structures could deeply affect the life of isolated disc galaxies, by shaping their stellar and gaseous distribution, some fundamental aspects of their formation and growth are still debated. The following manuscript is divided in two parts, in which I contribute to the study of bar formation and evolution through the use of state-of-the-art hydrodynamical and cosmological simulations. In the first part of my work, I investigate the influence of tidal encounters on either unbarred, or already barred systems. Here, I take advantage of two specific simulations belonging to the Eris suite – ErisBH and Eris2k – which evolve two Milky Way-sized barred galaxies in their cosmological volume. I both analyse the direct output of these simulations, and run a sample of new cosmological zoom-in simulations, by altering the original history of galaxy-satellite interactions in the ErisBH run. In the second part, I focus on the analysis of the effect of the different feedback prescriptions implemented in the ErisBH and Eris2k runs. My conclusions depict a scenario where, once the disc has grown to a mass large enough to sustain global non-axisymmetric modes, bar formation is inevitable and tidal encounters have, a destructive effect on the two-fold overdensity. In addition, the self-gravity of the disc and its interplay with various internal processes, seem to be the main drivers of bar formation and growth. I confirm the importance of accurate feedback prescriptions in cosmological zoom-in simulations on the investigated processes, and propose a possible use of a statistical sample of barred galaxies to quantitatively assess this dependence.