Research > Projects > Closing the Circle: The First High-Resolution Panoramic View of the Milky Way Disk

The recent completion of the Outer Galaxy High-Resolution Survey (OGHReS) provides the most detailed view of the molecular gas across the MW disk, exploiting the synergies with its twin survey of the inner disk, SEDIGISM, and with HiGAL, to characterize the dust. With this unique dataset, we aim to develop a comprehensive understanding of how the environment shapes the molecular ISM and
influences star formation, key for galaxy evolution, and to establish a crucial anchor for interpreting extragalactic data.

Planned activities:
The project aims to provide the first high-resolution panoramic view of the Milky Way disk by leveraging the recently completed Outer Galaxy High-Resolution Survey (OGHReS). A primary focus of the activities is the systematic investigation of the gas-to-dust mass ratio and its dependence on the galactocentric radius and metallicity. By using OGHReS data alongside the SEDIGISM survey, the team will calculate total H2​ column densities from optically-thin C18O(2−1) emission, increasing source statistics by a factor of 20 compared to previous studies. This investigation is critical because it moves beyond assuming a canonical CO abundance; instead, the researchers will build chemical models with reduced metallicity and varying C/O ratios to see how CO responds to the outer Galaxy environment. These results will ultimately clarify whether dust evolution is driven primarily by stars or by interstellar condensation and coagulation, while also refining our understanding of star-formation efficiency across the Galactic disk.

Start: 2025
Duration: 1 anno
Financing program: Ricerca Fondamentale INAF
Referent: Andrea Giannetti (INAF)