Multiple phase spirals suggest multiple origins in Gaia DR3

Understand

{\it Gaia} Data Release 2 (DR2) revealed that the Milky Way contains significant indications of departures from equilibrium in the form of asymmetric features in the phase space density of stars in the Solar neighborhood.

• One such feature is the $z$--$v_z$ phase spiral, interpreted as the response of the disk to the influence of a perturbation perpendicular to the disk plane, which could be external (e.g., a satellite) or internal (e.g., the bar or spiral arms).
• In this work we use {\it Gaia} DR3 to dissect the phase spiral by dividing the local data set into groups with similar azimuthal actions, $J_\phi$, and conjugate angles, $\theta_\phi$, which selects stars on similar orbits and at similar orbital phases, thus having experienced similar perturbations in the past.
• These divisions allow us to explore areas of the Galactic disk larger than the surveyed region.