Ethynyl around the HII regions S255 and S257

Abstract

We present the results of the ethynyl (C2H) emission line observations towards the HII regions S255 and S257 and the molecular cloud between them. Radial profiles of line brightness, column density, and abundance of C2H are obtained. We show that the radial profile of the ethynyl abundance is almost flat towards the HII regions and drops by a factor of two towards the molecular cloud. At the same time, we find that the abundance of ethynyl is at maximum towards the point sources in the molecular cloud -- the stars with emission lines or emitting in X-ray. The line profiles are consistent with the assumption that both HII regions have front and back neutral walls that move relative to each other.

8 pages, accepted by Astronomy Reports

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Cited by in corpus (5)

• ATOMS: ALMA Three-millimeter Observations of Massive Star-forming regions -XIII. Ongoing triggered star formation within clump-fed scenario found in the massive ($\sim 1500$ ${\mathrm{M}}_{\odot }$) clump
• Dark cloud-type chemistry in PDRs with moderate UV field
• The link between gas and stars in the S254-S258 star-forming region
• Ammonia mapping observations toward the Galactic massive star-forming region Sh 2-255 and Sh 2-257
• Near infrared view on the photodissociation regions S255, S257, NGC7538 and S140