Studies of the distinct regions due to CO selective dissociation in the Aquila molecular cloud

Abstract

Aims. We investigate the role of selective dissociation in the process of star formation by comparing the physical parameters of protostellar-prestellar cores and the distinct regions with the CO isotope distributions in photodissociation regions. We seek to understand whether there is a better connection between the evolutionary age of star forming regions and the effect of selective dissociation Methods. Wide-field observations of the ${}^{12}\mathrm{CO}$, ${}^{13}\mathrm{CO}$, and ${\mathrm{C}}^{18}\mathrm{O}$ ( J = 1 - 0) emission lines are used to study the ongoing star formation activity in the Aquila molecular region, and the 70 $\mu$m and 250 $\mu$m data are used to describe the heating of the surrounding material and as an indicator of the evolutionary age of the core. Results. The protostellar-prestellar cores are found at locations with the highest ${\mathrm{C}}^{18}\mathrm{O}$ column densities and their increasing evolutionary age would relate to an increasing 70$\mu$m/250$\mu$m emission ratio at their location. An evolutionary age of the cores may also follow from the ${}^{13}\mathrm{CO}$ versus ${\mathrm{C}}^{18}\mathrm{O}$ abundance ratio, which decreases with increasing ${\mathrm{C}}^{18}\mathrm{O}$ column densities. The original mass has been estimated for nine representative star formation regions and the original mass of the region correlated well with the integrated 70 $\mu$m flux density. Similarly, the $X_{{}^{13}\mathrm{CO}}$/$X_{{\mathrm{C}}^{18}\mathrm{O}}$ implying the dissociation rate for these regions correlates with the 70$\mu$m/250$\mu$m flux density ratio and reflects the evolutionary age of the star formation activity.

arXiv comment10 pages

References in corpus (16)

• From filamentary clouds to prestellar cores to the stellar IMF: Initial highlights from the Herschel Gould Belt survey
• Characterizing interstellar filaments with Herschel in IC5146
• Herschel view of the Taurus B211/3 filament and striations: Evidence of filamentary growth?
• The relation between gas and dust in the Taurus Molecular Cloud
• A census of dense cores in the Aquila cloud complex: SPIRE/PACS observations from the Herschel Gould Belt survey
• The Spitzer Gould Belt Survey of Large Nearby Interstellar Clouds: Discovery of a Dense Embedded Cluster in the Serpens-Aquila Rift
• The Herschel first look at protostars in the Aquila Rift
• The Gould's Belt Distances Survey (GOBELINS) III. The distance to the Serpens/Aquila Molecular Complex
• High abundance ratio of ${}^{13}$CO to C${}^{18}$O toward photon-dominated regions in the Orion-A giant molecular cloud
• Formation, fractionation and excitation of carbon monoxide in diffuse clouds
• The identification of dust heating mechanisms in nearby galaxies using Herschel 160/250 and 250/350 micron surface brightness ratios
• The Relationship Between the Dust and Gas-Phase CO Across the California Molecular Cloud
• The intrinsic abundance ratio and X-factor of CO isotopologues in L1551 shielded from FUV photodissociation
• Local Molecular Gas toward the Aquila Rift Region
• ${\mathrm{H}}_2\mathrm{CO}$ and $H110\alpha$ Observations toward the Aquila Molecular Cloud
• The James Clerk Maxwell Telescope Nearby Galaxies Legacy Survey IX: ${}^{12}$CO $J=3\to 2$ Observations of NGC 2976 and NGC 3351

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