Star-forming content of the giant molecular filaments in the Milky Way
AffiliationUniv Arizona, Dept Astron
MetadataShow full item record
PublisherEDP SCIENCES S A
CitationZhang, M., Kainulainen, J., Mattern, M., Fang, M., & Henning, T. (2019). Star-forming content of the giant molecular filaments in the Milky Way. Astronomy & Astrophysics, 622, A52.
JournalASTRONOMY & ASTROPHYSICS
Rights© ESO 2019
Collection InformationThis item from the UA Faculty Publications collection is made available by the University of Arizona with support from the University of Arizona Libraries. If you have questions, please contact us at firstname.lastname@example.org.
AbstractThrough observations numerous giant molecular filaments (GMFs) have been discovered in the MilkyWay. Their role in the Galactic star formation and Galaxy-scale evolution of dense gas is unknown. Aims. We investigate systematically the star-forming content of all currently known GMFs. This allows us to estimate the star formation rates (SFRs) of the GMFs and to establish relationships between the SFRs and the GMF properties. Methods. We identified and classified the young stellar object (YSO) population of each GMF using multiwavelength photometry from near-to far-infrared. We estimated the total SFRs assuming a universal and fully sampled initial mass function and luminosity function. Results. We uniformly estimate the physical properties of 57 GMFs. The GMFs show correlations between the (CO)-C-13 line width, mass, and size, similar to Larson's relations. We identify 36 394 infrared excess sources in 57 GMFs and obtain SFRs for 46 GMFs. The median SFR surface density (Sigma(SFR)) and star formation efficiency (SFE) of GMFs are 0.62 M-circle dot Myr(-1) pc(-2) and 1%, similar to the nearby star-forming clouds. The star formation rate per free-fall time of GMFs is between 0.002-0.05 with the median value of 0.02. We also find a strong correlation between SFR and dense gas mass that is defined as gas mass above a visual extinction of 7 mag, which suggests that the SFRs of the GMFs scale similarly with dense gas as those of nearby molecular clouds. We also find a strong correlation between the mean SFR per unit length and dense gas mass per unit length. The origin of this scaling remains unknown, calling for further studies that can link the structure of GMFs to their SF activity and explore the differences between GMFs and other molecular clouds.
NoteOpen access journal.
VersionFinal published version
SponsorsEuropean Union's Horizon 2020 research and innovation program ; National Natural Science Foundation of China ; National Aeronautics and Space Administration; Science and Technology Facilities Council of the UK; National Science Foundation [AST-9800334, AST-0098562, AST-0100793]