Low surface brightness galaxies in the SKA era

Low Surface Brightness galaxies (LSBs), with disk central surface brightness typically below 23 mag/arcsec2, could represent a large fraction of galaxies. Their evolution and their role in the overall picture of galaxy formation and evolution is still under debate. Amongst them, ultra-diffuse galaxies (UDGs), with optical luminosity typical of dwarf galaxies but effective radius comparable to that of the Milky Way, have recently undergone a revival of interest as deep imaging observations revealed their ubiquity both in groups and clusters and in the field. While UDGs may harbor a diversity of atomic HI gas content, giant LSBs are usually gas rich. In all cases, HI measurements at different redshifts will be crucial to understand their evolution. The Square Kilometer Array (SKA), whose construction started last Summer, will allow HI gas measurements up to intermediate redshifts z~1 and hence shed light on the formation and evolution of LSBs and UDGs. In this workshop, proposed by the Association Specifique SKA-LOFAR (https://as-ska-lofar.fr/), we would like to gather researchers in France or with strong ties with the French community working on LSBs and UDGs and more generally the low surface brightness universe, to prepare for the arrival of SKA. This workshop is intended to widen the community interested in the SKA preparation, so researchers not involved in radioastronomy are also particularly welcome.