Nuclear spirals in the inner Milky Way

Journal article

We use hydrodynamical simulations to construct a new coherent picture for the gas flow in the Central Molecular Zone (CMZ), the region of our Galaxy within R ≲ 500  pc. We relate connected structures observed in (l, b, v) data cubes of molecular tracers to nuclear spiral arms. These arise naturally in hydrodynamical simulations of barred galaxies, and are similar to those that can be seen in external galaxies such as NGC 4303 or NGC 1097. We discuss a face-on view of the CMZ, including the positions of several prominent molecular clouds, such as Sgr B2, the 20 and 50 km s−1 clouds, the polar arc, Bania Clump 2 and Sgr C. Our model is also consistent with the larger scale gas flow, up to R ≃ 3 kpc, thus providing a consistent picture of the entire Galactic bar region.

Authors: Ridley, M; Sormani, M; Treß, R; Magorrian, J; Klessen, R

• Publication status: Published
• Peer review status: Peer reviewed
• Publisher: Oxford University Press
• Journal: Monthly Notices of the Royal Astronomical Society
• Volume: 469
• Issue: 2
• Pages: 2251-2262
• Publication date: 2017-04-21
• Acceptance date: 2017-04-18
• DOI: 10.1093/mnras/stx944
• EISSN: 1365-2966
• ISSN: 0035-8711
• Keywords: galaxies: kinematics and dynamics; ISM: kinematics and dynamics