Cloud Structure of Galactic OB Cluster Forming Regions from Combining Ground and Space Based Bolometric Observations

Abstract

We have developed an iterative procedure to systematically combine the millimeter and submillimeter images of OB cluster-forming molecular clouds, which were taken by ground based (CSO, JCMT, APEX, IRAM-30m) and space telescopes (Herschel, Planck). For the seven luminous ($L$$>$10${}^6$ $L_{\odot }$) Galactic OB cluster-forming molecular clouds selected for our analyses, namely W49A, W43-Main, W43-South, W33, G10.6-0.4, G10.2-0.3, G10.3-0.1, we have performed single-component, modified black-body fits to each pixel of the combined (sub)millimeter images, and the Herschel PACS and SPIRE images at shorter wavelengths. The $\sim$10$"$ resolution dust column density and temperature maps of these sources revealed dramatically different morphologies, indicating very different modes of OB cluster-formation, or parent molecular cloud structures in different evolutionary stages. The molecular clouds W49A, W33, and G10.6-0.4 show centrally concentrated massive molecular clumps that are connected with approximately radially orientated molecular gas filaments. The W43-Main and W43-South molecular cloud complexes, which are located at the intersection of the Galactic near 3-kpc (or Scutum) arm and the Galactic bar, show a widely scattered distribution of dense molecular clumps/cores over the observed $\sim$10 pc spatial scale. The relatively evolved sources G10.2-0.3 and G10.3-0.1 appear to be affected by stellar feedback, and show a complicated cloud morphology embedded with abundant dense molecular clumps/cores. We find that with the high angular resolution we achieved, our visual classification of cloud morphology can be linked to the systematically derived statistical quantities (i.e., the enclosed mass profile, the column density probability distribution function, the two-point correlation function of column density, and the probability distribution function of clump/core separations).

ApJ accepted, Some figures in appendix are omitted

References in corpus (29)

• Power-law distributions in empirical data
• Cold Dark Clouds: The Initial Conditions for Star Formation
• Structural Analysis of Molecular Clouds: Dendrograms
• Filamentary structure of star-forming complexes
• On the Star Formation Efficiency of Turbulent Magnetized Clouds
• Molecular Cloud Evolution II. From cloud formation to the early stages of star formation in decaying conditions
• The earliest phases of high-mass star formation: a 3 square degree millimeter continuum mapping of Cygnus X
• SCUBA-2: iterative map-making with the Sub-Millimetre User Reduction Facility
• The Large APEX Bolometer Camera LABOCA
• On the Density Distribution in Star-forming Interstellar Clouds
• Before the first supernova: combined effects of HII regions and winds on molecular clouds
• The Perils of Clumpfind: The Mass Spectrum of Sub-structures in Molecular Clouds
• Molecular clouds have power-law probability distribution functions
• Submillimetre point sources from the Archeops experiment: Very Cold Clumps in the Galactic Plane
• Understanding star formation in molecular clouds I. Effects of line-of-sight contamination on the column density structure
• A cluster in the making: ALMA reveals the initial conditions for high-mass cluster formation
• Hierarchical Star Formation in the Spiral Galaxy NGC 628
• Spatial Distributions of Young Stars
• ALMA resolves the spiraling accretion flow in the luminous OB cluster forming region G33.92+0.11
• Understanding star formation in molecular clouds II. Signatures of gravitational collapse of IRDCs
• The W43-MM1 mini-starburst ridge, a test for star formation efficiency models
• Hierarchical Star Formation in Nearby LEGUS Galaxies
• The fractal dimension of star-forming regions at different spatial scales in M33
• Millimetre Continuum Observations of Southern Massive Star Formation Regions II. SCUBA observations of cold cores and the dust grain emissivity index $\beta$
• Diversity of chemistry and excitation conditions in the high-mass star forming complex W33
• Massive Stars in the W33 Giant Molecular Complex
• The Nature of the Gould Belt from a Fractal Analysis of its Stellar Population
• The Discovery of a Very Massive Star in W49
• G-virial: Gravity-based structure analysis of molecular clouds

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• Globular Cluster Formation at High Density: A model for Elemental Enrichment with Fast Recycling of Massive-Star Debris
• Magnetized interstellar molecular clouds: II. The Large-Scale Structure and Dynamics of Filamentary Molecular Clouds
• FOREST Unbiased Galactic plane Imaging survey with the Nobeyama 45-m telescope (FUGIN) : Molecular clouds toward W33 ; possible evidence for a cloud-cloud collision triggering O star formation
• Kinetic temperature of massive star-forming molecular clumps measured with formaldehyde. III. The Orion Molecular Cloud 1
• The density structure of supersonic self-gravitating turbulence
• The chemical structure of young high-mass star-forming clumps: (II) parsec-scale CO depletion and deuterium fraction of $\mathrm{HC}{\mathrm{O}}^{+}$
• The evolution of temperature and density structures of OB cluster-forming molecular clumps
• J-comb: An image fusion algorithm to combine observations covering different spatial frequency ranges
• Large-scale Map of Millimeter-wavelength Hydrogen Radio Recombination Lines around a Young Massive Star Cluster
• ALMA reveals a pseudo-disc in a proto-brown dwarf
• Illuminating the Tadpole's metamorphosis I: MUSE observations of a small globule in a sea of ionizing photons
• On the evolution of the observed Mass-to-Length relationship for star-forming filaments
• Interpreting observations of edge-on gravitationally unstable accretion flows
• Spiral Structure and Massive Star formation in the Hub-Filament-System G326.27-0.49
• Complex structure of a proto-brown dwarf
• A Massive Young Runaway Star in W49 North
• Redshifted methanol absorption tracing infall motions of high-mass star formation regions
• Sub-arcsecond Imaging of the Complex Organic Chemistry in Massive Star-forming Region G10.6-0.4