“Dynamics of the Spiral Arms as Seen by Gaia DR3 and Simulations”
Although it is widely accepted that we live in a spiral galaxy, the location, population, and even the number of spiral arms remain controversial. These uncertainties arise from our position within the Milky Way disc, which prevents us from having a global view of the spiral structure, unlike external galaxies. To overcome this limitation, one must trace the spiral arms by means of more indirect methods, based on the imprints that the spirals leave on kinematics, dynamics, and chemistry, among other aspects. In this talk, I will present recent results from the Galactic Archaeology group at the Observatoire de la Côte d’Azur concerning the detection of the Milky Way’s spiral arms, with particular emphasis on those identified using Gaia DR3 radial actions and subsequently confirmed by numerical simulations.