The Dense Filamentary Giant Molecular Cloud G23.0-0.4: Birthplace of Ongoing Massive Star Formation

Abstract

We present observations of 1.5 square degree maps of the 12CO, 13CO, and C18O (J=1-0) emission toward the complex region of the supernova remnant (SNR) W41 and SNR G22.7-0.2. A massive (~5E5Msun), large (~84x15 pc), and dense (~10E3 cm^-3) giant molecular cloud (GMC), G23.0-0.4 with VLSR~77 km/s, is found to be adjacent to the two SNRs. The GMC displays a filamentary structure approximately along the Galactic plane. The filamentary structure of the dense molecular gas, traced by C18O (J=1-0) emission, is also coincident well with the distribution of the dust-continuum emission in the direction. Two dense massive MC clumps, two 6.7 GHz methanol masers, and one HII/SNR complex, associated with the 77 km/s GMC G23.0-0.4, are aligned along the filamentary structure, indicating the star forming activity within the GMC. These sources have periodic projected spacing of 0.18-0.26degree along the giant filament, which is consistent well with the theoretical predictions of 0.22degree. It indicates that the turbulence seems to dominate the fragmentation process of the dense gaseous filament on large scale. The established 4.4 kpc distance of the GMC and the long dense filament traced by C18O emission, together with the rich massive star formation groups in the nearby region, suggest that G23.0-0.4 is probably located at the near side of the Scutum-Centaurus arm in the first quadrant. Considering the large scale and the elongation structure along the Galactic plane, we speculate that the dense filamentary GMC has relation to the spiral density wave of the Milky Way.

28 preprint pages, 3 Tables, 9 Figures, accepted for publication in ApJ. Comments are welcome

References in corpus (15)

• Theory of Star Formation
• The Boston University-Five College Radio Astronomy Observatory Galactic Ring Survey
• The VLA Galactic Plane Survey
• Kinematic Distances to Molecular Clouds identified in the Galactic Ring Survey
• The Bones of the Milky Way
• Mutual influence of supernovae and molecular clouds
• The formation of molecular clouds in spiral galaxies
• Trigonometric Parallaxes of Massive Star Forming Regions: V. G23.01-0.41 and G23.44-0.18
• The Distances of SNR W41 and overlapping HII regions
• Colliding Filaments and a Massive Dense Core in the Cygnus OB 7 Molecular Cloud
• Probing the gamma-ray emission from HESS J1834-087 using H.E.S.S. and Fermi LAT observations
• Discovery of the VHE gamma-ray source HESS J1832-093 in the vicinity of SNR G22.7-0.2
• Fragmentation and Kinematics of dense molecular cores in the filamentary infrared-dark cloud G011.11-0.12
• Interaction Between Supernova Remnant G22.7-0.2 And The Ambient Molecular Clouds
• Massive stars in the giant molecular cloud G23.3-0.3 and W41

Cited by in corpus (13)

• The Milky Way Imaging Scroll Painting (MWISP): Project Details and Initial Results from the Galactic Longitude of 25.8deg to 49.7deg
• Molecular clouds and star formation toward the Galactic plane within 216.25${}^{\mathrm{o}}\le$ l $\le$218.75${}^{\mathrm{o}}$ and $-$0.75${}^{\mathrm{o}}\le$ b $\le$1.25${}^{\mathrm{o}}$
• Simultaneous evidence of edge collapse and hub-filament configurations: A rare case study of a Giant Molecular Filament G45.3+0.1
• Local Molecular Gas toward the Aquila Rift Region
• 12CO (3-2) High-Resolution Survey (COHRS) of the Galactic Plane: Complete Data Release
• Atlas of CO-Line Shells and Cavities around Galactic Supernova Remnants with FUGIN
• The Stellar "Snake" I: Whole Structure and Properties
• The Age Evolution of the Radio Morphology of Supernova Remnants
• Structures of GMC W 37
• The Interaction Between the Supernova Remnant W41 and the Filamentary Infrared Dark Cloud G23.33-0.30
• The discovery of the largest gas filament in our Galaxy, or a new spiral arm?
• Revealing Gas Inflows towards the Galactic Central Molecular Zone
• Multiwavelength study of non-thermal emission in the Swift J1834.9-0846/W41 region