« Faint but not forgotten: what simulations reveal about Low Surface Brightness Galaxies »
Low Surface Brightness Galaxies (LSBGs) constitute a substantial fraction of galaxies in the local Universe, being primarily bulge-less, late-type galaxies, bluer and more gas-rich than their high surface brightness counterparts (HSBG). In this talk I will explore the nature of this kind of galaxies, confronting the results of hydrodynamic cosmological simulations with large observational samples. We show that LSBGs span a wide range of stellar masses and tend to be more extended and less massive than their high surface brightness counterparts. Their distinct structural properties are closely linked to their higher specific angular momentum and halo spin parameters, which lead to suppressed central concentrations and lower-mass central black holes. We explore the environments of LSBGs, finding that while large-scale cosmic web structures do not play a dominant role, local environmental effects —such as those found in groups and clusters— strongly influence LSBG morphology and abundance. In particular, rotation-dominated LSBGs prefer low-density environments, whereas dispersion-dominated ones are more common in high-density regions, suggesting different evolutionary pathways driven by local interactions. Finally, we examine the incidence of stellar bars in LSBGs and find that their lower bar fraction, relative to HSBGs, can be attributed primarily to their higher spin and gas content. Interestingly, tidal interactions —while having limited impact overall— appear to enhance bar formation in LSBGs more than in HSBGs. These results offer a unified picture in which the internal properties of LSBGs, combined with local environmental influences, shape their structural and dynamical evolution.