The three-dimensional structure of Galactic molecular cloud complexes out to 2.5 kpc

Abstract

Knowledge of the three-dimensional structure of Galactic molecular clouds is important for understanding how clouds are affected by processes such as turbulence and magnetic fields and how this structure effects star formation within them. Great progress has been made in this field with the arrival of the Gaia mission, which provides accurate distances to $\sim 10^9$ stars. Combining these distances with extinctions inferred from optical-IR, we recover the three-dimensional structure of 16 Galactic molecular cloud complexes at $\sim 1$pc resolution using our novel three-dimensional dust mapping algorithm \texttt{Dustribution}. Using \texttt{astrodendro} we derive a catalogue of physical parameters for each complex. We recover structures with aspect ratios between 1 and 11, i.e.\ everything from near-spherical to very elongated shapes. We find a large variation in cloud environments that is not apparent when studying them in two-dimensions. For example, the nearby California and Orion A clouds look similar on-sky, but we find California to be more sheet-like, and massive, which could explain their different star-formation rates. In Carina, our most distant complex, we observe evidence for dust sputtering, which explains its measured low dust mass. By calculating the total mass of these individual clouds, we demonstrate that it is necessary to define cloud boundaries in three-dimensions in order to obtain an accurate mass; simply integrating the extinction overestimates masses. We find that Larson's relationship on mass vs radius holds true whether you assume a spherical shape for the cloud or take their true extents.

accepted for publication by MNRAS, 23 pages, 9 figures, 3 tables

References in corpus (18)

• The Gaia mission
• Gaia-2MASS 3D maps of Galactic interstellar dust within 3 kpc
• A Large Catalog of Accurate Distances to Local Molecular Clouds: The Gaia DR2 Edition
• A Compendium of Distances to Molecular Clouds in the Star Formation Handbook
• A Galactic-scale gas wave in the Solar Neighborhood
• FellWalker - a Clump Identification Algorithm
• On the Three-Dimensional Structure of Local Molecular Clouds
• Structure and mass segregation in Galactic stellar clusters
• Herschel's view of the large-scale structure in the Chamaeleon dark clouds
• The Per-Tau Shell: A Giant Star-Forming Spherical Shell Revealed by 3D Dust Observations
• Lupus DANCe. Census of stars and 6D structure with Gaia-DR2 data
• High Velocity Features in the Orion Nebula
• HP2 survey: III The California Molecular Cloud--A Sleeping Giant Revisited
• 3D Dust Mapping Reveals that Orion Forms Part of a Large Ring of Dust
• Three-dimensional dust density structure of the Orion, Cygnus X,Taurus, and Perseus star-forming regions
• FEDReD II : 3D Extinction Map with 2MASS and Gaia DR2 data
• The substructure of the Perseus star forming region: A survey with Gaia DR2
• FEDReD III : Unraveling the 3D structure of Vela

Cited by in corpus (8)

• PHANGS-JWST First Results: The Dust Filament Network of NGC 628 and its Relation to Star Formation Activity
• A Parsec-Scale Catalog of Molecular Clouds in the Solar Neighborhood Based on 3D Dust Mapping: Implications for the Mass-Size Relation
• A panoptic view of the Taurus molecular cloud I. The cloud dynamics revealed by gas emission and 3D dust
• Cloud properties across spatial scales in simulations of the interstellar medium
• The Solar System's passage through the Radcliffe wave during the middle Miocene
• SRG/eROSITA 3D mapping of the ISM using X-ray absorption spectroscopy
• A High-Mass Young Star-forming Core Escaping from Its Parental Filament
• Improved source classification and performance analysis using Gaia DR3