The ins and outs of edge-on galaxies: insights from the GECKOS MUSE survey

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. However, 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 structural components – remains elusive. In this talk, I will present the first results of the GECKOS survey, an ESO VLT/MUSE large program. The main aim of GECKOS is to reveal the variation in key physical processes of disk formation by connecting Galactic and extragalactic galaxies. Edge-on galaxies are ideal for this task: they allow us to disentangle the assembly history imprinted in thick disks and provide the greatest insights into outflows. The GECKOS sample of 35 nearby, edge-on disk galaxies is designed to determine the assembly histories and properties of galaxies across a large range of SFRs, B/T ratios, and boxy and non-boxy bulges. At this meeting, I will present the richness of the IFS data, with 2D measurements of stellar abundance, age, and kinematics, as well as ionised gas metallicities, ionisation parameters, and outflow kinematics; all core ingredients for chemical evolution models. With these data, we aim to extend Galactic methods to the wider galaxy population, reaping the benefits of detailed Milky Way studies, while probing the diverse mechanisms of galaxy evolution.