Evolutionary Mechanisms in the Milky waY: the Gaia Data Release 3 revolution

The understanding of our home Galaxy stands at a crossroads.

Thanks to the Gaia mission of the European Space Agency, combined with ground-based surveys, previously unexplored portions of the Milky Way have recently been mapped, opening a new era in Galactic Astronomy and Astrophysics. In 2022, Gaia Data Release 3 will publish the largest chemical and radial velocity stellar catalog ever created.

For the first time, chemical abundances of stellar atmospheres will be linked to the positions and motions of stars over the entire sky.

Taking advantage of the unprecedented wealth of chemo-dynamical data, the EMMY project aims to tackle outstanding questions about the mutual interplay of different evolutionary mechanisms in the Galactic disc, including the influence of the Milky Ways satellite galaxies, along with secular evolutionary processes.

Specifically, the EMMY project aims to: 1) map chemo-dynamical inhomogeneities in the Galactic disc; 2) determine the extent to which the observed inhomogeneities can be attributed to internal processes, such as the actions of the spiral arms or the bar; 3) constrain the role of external influences, such as satellite interactions, on the disc evolution.

The objectives will be assessed through an optimised Galactic cartography, which will link inhomogeneities in stellar density, velocity, chemistry; observational results will be then compared to cosmological simulations and chemical evolution models, to constrain spiral arms formation scenarios and disc heating processes.

The multidisciplinary nature of the project is strong, combining interdisciplinary knowledge of astronomy, physics, statistics, data mining, and big data analysis.

The results of the proposed project are expected to give a cohesive, statistically robust, accurate, and informative picture of the physical processes in the Galactic disc, which have the potential to represent an important contribution to our understanding of the Galaxy and its place in the Universe.