Abstract

The galactic bar is a common structure in the Universe; approximately two-thirds of spiral galaxies host a bar at their centers. Due to its non-axisymmetric nature, the galactic bars influence not only the dynamics of the surrounding stars but also reshape the galactic disk and halo. Therefore, understanding galactic bars is crucial for telling the story of galaxy evolution in general. Our Milky Way provides a unique opportunity to study the kinematics and dynamics of the Galactic bar in detail, as we can resolve individual stars in phase space. By complementing the kinematics of stars with ages, we have chances to decode the history of the inner Galaxy. We present the chrono-kinematic signature of the inner Galaxy traced by Mira variable stars. Observing the evolution of bar morphology and kinematics with age allows us to explore the heating history of the inner Milky Way. We establish a connection between the bar chrono-kinematic evolution and the formation of the Galactic disk, providing a novel and independent constraint on the epoch of the Milky Way disk formation.