Ammonia mapping observations toward the Galactic massive star-forming region Sh 2-255 and Sh 2-257

Abstract

We performed NH${}_3(J,K)=(1,1),(2,2),$ and $(3,3)$ mapping observations toward the Galactic massive star-forming region Sh 2-255 and Sh 2-257 using the Nobeyama 45-m telescope as a part of the KAGONMA (KAgoshima Galactic Object survey with the Nobeyama 45-metre telescope by Mapping in Ammonia lines) project. NH${}_3$ (1,1) has an intensity peak at the cluster S255 N, is distributed over 3 pc $\times$ 2 pc and is located between two HII regions. The kinetic temperature derived from the NH${}_3(2,2)/(1,1)$ ratio was $\sim 35$ K near the massive cluster S255 IR. These clusters also show emission with a large line width of $\sim$ 3-4 km s${}^{-1}$. Based on the reported data we suggest that NH${}_3$ gas in these regions is affected by stellar feedback from embedded YSO clusters in S255 IR and S255 N. We also detected NH${}_3$ (1,1) emission in a region west of the main gas clump at the location of a concentration of Class II YSOs adjacent to the HII regions Sh 2-254. The presence of Class II YSOs implies $\sim$ 2 Myr of star formation, younger than Sh 2-254 ($\sim 5$ Myr), thus we suggest that star formation in the western region could be influenced by the older HII region Sh 2-254.

arXiv comment20 pages, 8 figures, 3 tables, accepted for Publications of the Astronomical Society of Japan (PASJ)

References in corpus (42)

• Astropy: A Community Python Package for Astronomy
• The NumPy array: a structure for efficient numerical computation
• The Wide-field Infrared Survey Explorer (WISE): Mission Description and Initial On-orbit Performance
• The Astropy Project: Building an inclusive, open-science project and status of the v2.0 core package
• MAMBO Mapping of Spitzer c2d Small Clouds and Cores
• How to Calculate Molecular Column Density
• A Large Catalog of Accurate Distances to Local Molecular Clouds: The Gaia DR2 Edition
• Disk-mediated accretion burst in a high-mass young stellar object
• The RMS Survey: Ammonia and water maser analysis of massive star forming regions
• Trigonometric Parallaxes of 6.7 GHz Methanol Masers
• Star-forming protoclusters associated with methanol masers
• Digital Spectro-Correlator System for the Atacama Compact Array of the Atacama Large Millimeter/submillimeter Array
• H2O masers in a jet-driven bowshock: Episodic ejection from a massive young stellar object
• Spitzer observations of the Massive star forming complex S254-S258: structure and evolution
• The Bolocam Galactic Plane Survey -- III. Characterizing Physical Properties of Massive Star-Forming Regions in the Gemini OB1 Molecular Cloud
• Different Evolutionary Stages in the Massive Star Forming Region S255 Complex
• Radio outburst from a massive (proto)star. When accretion turns into ejection
• The disk-outflow system in the S255IR area of high mass star formation
• Giant burst of methanol maser in S255IR-NIRS3
• Chemical differentiation in regions of high mass star formation II. Molecular multiline and dust continuum studies of selected objects
• Star Formation Activity in the Galactic HII Complex S255-S257
• A Submillimeter Burst of S255IR~SMA1 - The Rise And Fall Of Its Luminosity
• A multiwavelength study of embedded clusters in W5-east, NGC7538, S235, S252 and S254-S258
• Evidence for a Massive Protocluster in S255N
• A Multi-Wavelength High Resolution Study of the S255 Star Forming Region. General structure and kinematics
• ALMA View of the Infalling Envelope around a Massive Protostar in S255IR SMA1
• ATLASGAL - Ammonia observations towards the southern Galactic Plane
• Star formation in the filament of S254-S258 OB complex: a cluster in the process of making
• Dense Cores, Filaments and Outflows in the S255IR Region of High Mass Star Formation
• A Complete Survey of the Central Molecular Zone in NH3
• NH3 in the Central 10 pc of the Galaxy. II. Determination of Opacity for Gas with Large Linewidths
• Near-infrared Monitoring of the Accretion Outburst in the MYSO S255-NIRS3
• Water maser variability in a high-mass YSO outburst -- VERA and ALMA observations of S255 NIRS 3
• Interaction Between HII Region and AFGL333-Ridge: Implications to the Star Formation Scenario
• Molecular gas toward the Gemini OB1 Giant Molecular Cloud Complex I: Observation data
• Propagation of Highly Efficient Star Formation in NGC 7000
• NH3 in the Galactic Center is formed in Cool Conditions
• The link between gas and stars in the S254-S258 star-forming region
• The RMS Survey: Ammonia mapping of the environment of young massive stellar objects II
• NH${}_3$ Observations of the S235 Star Forming Region: Dense Gas in Inter-core Bridges
• Ethynyl around the HII regions S255 and S257
• The Spatial-Kinematic Structure of the Region of Massive Star Formation S255N on Various Scales

Cited by in corpus (5)

• High energy gamma-ray emission powered by a young protostar: the case of S255 NIRS 3
• Imaging Molecular Outflow in Massive Star-forming Regions with HNCO Lines
• 3D structure of HII regions in the star-forming complex S254-S258
• Ammonia mapping observations of the Galactic infrared bubble N49: Three NH${}_3$ clumps along the molecular filament
• KAgoshima Galactic Object survey with Nobeyama 45-metre telescope by Mapping in Ammonia lines (KAGONMA): Discovery of parsec-scale CO depletion in the Canis Major star-forming region