The RMS Survey: ${}^{13}$CO observations of candidate massive YSOs in the northern Galactic plane

Abstract

Context: The Red MSX Source (RMS) survey is an ongoing multi-wavelength observational programme designed to return a large, high-resolution mid-infrared colour-selected sample of massive young stellar objects. Aims: A critical part of our follow-up programme is to conduct 13CO molecular line observations in order to determine kinematic distances to all of our MYSO candidates. These distances will allow us to identify and remove nearby low-mass YSOs and help in identifying evolved stars which are weak CO emitters. Method: We have used the 15 m James Clerk Maxwell Telescope (JCMT), the 13.7 m telescope of the Purple Mountain Observatory (PMO), the 20 m Onsala telescope and the 22m Mopra telescope to conduct molecular line observations towards 508 MYSOs candidates located in the 1st and 2nd Quadrants. Results: We detect 13CO emission towards 780 RMS sources which corresponds to approximately 84% of those observed (911). A total of 2595 emission components are detected above 3sigma level (typically T^*_{\rm{A}} > 0.3K), with multiple components being observed towards the majority of these sources -- 520 sources (~56%) -- with an average of ~4 molecular clouds detected along each line of sight. We have used archival CS (J=2-1) and maser velocities to resolve the component multiplicity towards 175 sources (~20%) and have derived a criterion which is used to identify the most likely component for a further 191 multiple component sources. Combined with the single component detections we have obtained unambiguous kinematic velocities for 638 of the 780 MYSOs candidates towards which CO is detected (~80% of the detections). Using the Galactic rotation curve we calculate kinematic distances for all detected components.

arXiv comment13 pages and 9 figures, accepted for publication in A&A. Includes a large table and figure to be made available via CDS

References in corpus (15)

• The Milky Way in Molecular Clouds: A New Complete CO Survey
• GLIMPSE: I. A SIRTF Legacy Project to Map the Inner Galaxy
• The Boston University-Five College Radio Astronomy Observatory Galactic Ring Survey
• High-Mass Proto-Stellar Candidates - I : The Sample and Initial Results
• Infrared Dark Clouds: precursors to star clusters
• The earliest phases of high-mass star formation: a 3 square degree millimeter continuum mapping of Cygnus X
• A study of high velocity molecular outflows with an up-to-date sample
• A general catalogue of 6.7 GHz methanol masers. I: data
• The Population of the Galactic Plane as Seen by MSX
• Search for massive protostar candidates in the southern hemisphere: II. Dust continuum emission
• The RMS Survey: Radio observations of candidate massive YSOs in the southern hemisphere
• The RMS Survey: Mid-Infrared Observations of Candidate Massive YSOs in the Southern Hemisphere
• Search for massive protostellar candidates in the southern hemisphere: I. Association with dense gas
• Resolving the Kinematic Distance Ambiguity of Southern Massive Young Stellar Object Candidates
• Evidence for variable outflows in the Young Stellar Object V645 Cygni

Cited by in corpus (54)

• The WISE Catalog of Galactic HII Regions
• ATLASGAL --- properties of a complete sample of Galactic clumps
• The Red MSX Source Survey: the Massive Young Stellar Population of our Galaxy
• ATLASGAL --- towards a complete sample of massive star forming clumps
• The ATLASGAL survey: a catalog of dust condensations in the Galactic plane
• The RMS Survey: Ammonia and water maser analysis of massive star forming regions
• The RMS Survey: 6 cm continuum VLA observations towards candidate massive YSOs in the northern hemisphere
• The RMS Survey: Galactic distribution of massive star formation
• The RMS Survey: Critical Tests of Accretion Models for the Formation of Massive Stars
• ATLASGAL --- properties of compact HII regions and their natal clumps
• The Luminosity Functions and Timescales of MYSOs and Compact HII regions
• ATLASGAL -- A Galaxy-wide sample of dense filamentary structures
• The RMS Survey: The Bolometric Fluxes and Luminosity Distributions of Young Massive Stars
• The Slope of the Near Infrared Extinction Law
• The RMS Survey: Near-IR Spectroscopy of Massive Young Stellar Objects
• CO bandhead emission of massive young stellar objects: determining disc properties
• UWISH2 -- The UKIRT Widefield Infrared Survey for H2
• Trigonometric Parallaxes of Massive Star Forming Regions: G012.88+0.48 and W33
• The RMS Survey: Distribution and properties of a sample of massive young stars
• The RMS Survey: Resolving kinematic distance ambiguities towards a sample of compact HII regions using HI absorption
• A String of Radio Emission Associated with IRAS 16562-3959: A Collimated Jet Emanating from a Luminous Massive YSO
• Probing discs around massive young stellar objects with CO first overtone emission
• The RMS Survey: H2O masers towards a sample of southern hemisphere massive YSO candidates and ultra compact HII regions
• Diversity of chemistry and excitation conditions in the high-mass star forming complex W33
• A Mid-Infrared Census of Star Formation Activity in Bolocam Galactic Plane Survey Sources
• A distance limited sample of massive star forming cores from the RMS survey
• The RMS Survey: Ammonia mapping of the environment of massive young stellar objects
• A Survey of Extended H${}_2$ Emission from Massive YSOs
• YSO jets in the Galactic Plane from UWISH2: II - Outflow Luminosity and Length distributions in Serpens and Aquila
• Properties of Star Clusters - I: Automatic Distance and Extinction Estimates
• SEDIGISM-ATLASGAL: Dense Gas Fraction and Star Formation Efficiency Across the Galactic Disk
• The G305 star-forming complex: Embedded Massive Star Formation Discovered by Herschel Hi-GAL
• A Galactic survey of radio jets from massive protostars
• A 95 GHz Class I Methanol Maser Survey Toward A Sample of GLIMPSE Point Sources Associated with BGPS Clumps
• The RMS Survey: Far-Infrared Photometry of Young Massive Stars
• 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}}$
• The Interstellar Bubbles of G38.9-0.4 and the Impact of Stellar Feedback on Star Formation
• A hot molecular outflow driven by the ionized jet associated with IRAS 16562-3959
• Distinguishing post-AGB impostors in a sample of pre-main sequence stars
• Molecular cloud distance determination from deep NIR survey extinction measurements
• Chemical evolution of Red MSX Sources in the southern sky
• Testing the global star formation relation: An HCO+ (3-2) mapping study of Red MSX sources in the Bolocam Galactic Plane Survey
• Determining the Age of Young Embedded Clusters
• MALT90 molecular content on high-mass IR-dark clumps
• The RMS Survey: Ammonia mapping of the environment of young massive stellar objects II
• Molecular line study of massive star forming regions from the RMS survey
• Probing the Global Dust Properties and Cluster Formation Potential of the Giant Molecular Cloud G148.24+00.41
• WISE Discovery of Mid-infrared Variability in Massive Young Stellar Objects
• Physical and chemical properties of Red MSX Sources in the southern sky: HII regions
• A census of young stellar objects in two line-of-sight star forming regions toward IRAS 22147+5948 in the outer Galaxy
• Milliarcsecond structure of water maser emission in two young high-mass stellar objects associated with methanol masers
• Herschel Hi-GAL imaging of massive young stellar objects
• Investigating the morphology and CO gas kinematics of Sh2-112 region
• Search for High-Mass Protostellar Objects in Cold IRAS Sources