EPoS Contribution
EPoS Contribution
Automated identification of large-scale velocity-coherent filaments in the Galaxy

Ke Wang
ESO, Munich, DE
On the upper end of the filamentary hierarchy of the interstellar medium are large-scale gaseous filaments (10-100 pc). What is their distribution in our Galaxy and what role they play in Galactic star formation? Answer to the question is important for a critical comparison with theoretical studies. Since EPoS 2014, several groups have made progress in identifying and characterizing more filaments using different methods, either through targeted or blinded searches. However, all those methods rely on manual visual inspection and have been applied to a small fraction of the Galactic plane. Inherent bias and small Galactic coverage of these studies make it difficult to derive robust cross comparison and conclusive statistics.
We have developed an algorithm to automate the identification process, by connecting voxels in the position-position-velocity space using data from Galactic plane surveys. We have identified 56 large-scale filaments and derived mass, length, linearity, velocity gradient, temperature, fragmentation, Galactic location and orientation angle. The filaments are widely distributed across the Galactic disk, with 55% located within ± 20 pc from the Galactic mid-plane. This sample of filaments provides the first comprehensive catalog for comparison with spiral arm models and numerical simulations of filamentary cloud formation.
L. Testi, ESO, DE
A. Ginsburg, ESO, DE
C.M. Walmsley, INAF, IT
S. Molinari, INAF, IT
E. Schisano, INAF, IT
Key publication

Suggested Session: Filaments