The GECKOS Survey: Turning galaxy evolution on its side with deep observations of edge-on galaxies with and without bars

Due to the complexity of internal and external processes acting on disk galaxies, many outstanding questions regarding their evolution remain. Our Milky Way provides an unparalleled view of disk evolution but despite the wealth of data from the Galaxy, the origin of its different chemical components – the alpha rich and poor disk and their connection to the Galactic bar – remains elusive. In this talk I will present the first results of the GECKOS survey, a new ESO VLT/MUSE large program. One the aims of GECKOS is to reveal the impact of bars in changing the dynamical and chemical properties of disk galaxies like the Milky Way. Edge-on galaxies are ideal for this task: vertical boxy-peanut bar structures act as time capsules that allow us to determine the radial metallicity gradients present in the disk at the time of bar formation. The GECKOS sample of 35 nearby, edge-on disk galaxies with similar mass as the Milky Way, was designed to determine the differences between galaxies with and without a bar based on their boxy versus non-boxy central components. At this meeting, I will present exciting early results from the survey’s first semester IFS data, with 2D measurements of stellar abundance, age, and kinematics; all core ingredients for understanding the link between chemical evolution and the presence of a bar. With these data, we aim to extend Galactic methods to the wider galaxy population, reaping the benefits of detailed Milky Way studies on the Galactic bar, while probing the diverse formation mechanisms of bars in external galaxies.