THE MAGELLANIC MOPRA ASSESSMENT (MAGMA). I. THE MOLECULAR CLOUD POPULATION OF THE LARGE MAGELLANIC CLOUD

By T. Wong, Annie Hughes, J. Ott, E. Muller, J. Pineda, J. Bernard, Y. Chu, Y. Fukui, Robert A. Gruendl, C. Henkel and 29 more. 2011

200 citations recorded by the source corpus.

We present the properties of an extensive sample of molecular clouds in the Large Magellanic Cloud (LMC) mapped at 11 pc resolution in the CO(1–0) line. Targets were chosen based on a limiting CO flux and peak brightness as measured by the NANTEN survey. The observations were conducted with the ATNF Mopra Telescope as part of the Magellanic Mopra Assessment. We identify clouds as regions of connected CO emission and find that the distributions of cloud sizes, fluxes, and masses are sensitive to the choice of decomposition parameters. In all cases, however, the luminosity function of CO clouds is steeper than dN/dL∝L−2, suggesting that a substantial fraction of mass is in low-mass clouds. A correlation between size and linewidth, while apparent for the largest emission structures, breaks down when those structures are decomposed into smaller structures. We argue that the correlation between virial mass and CO luminosity is the result of comparing two covariant quantities, with the correlation appearing tighter on larger scales where a size–linewidth relation holds. The virial parameter (the ratio of a cloud's kinetic to self-gravitational energy) shows a wide range of values and exhibits no clear trends with the CO luminosity or the likelihood of hosting young stellar object (YSO) candidates, casting further doubt on the assumption of virialization for molecular clouds in the LMC. Higher CO luminosity increases the likelihood of a cloud harboring a YSO candidate, and more luminous YSOs are more likely to be coincident with detectable CO emission, confirming the close link between giant molecular clouds and massive star formation.

Subfields: Astronomy and Astrophysics

View Paper: https://www.semanticscholar.org/paper/1034dd71d600f4ece536579c9a2d470a329f050c

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Citations in the corpus

The CO-to-H2 Conversion Factor (2013, methodology): “Wong et al. (2011) estimate a very large scatter in avir in the Large Magellanic Cloud, but do lack an independent mass tracer so their results rest on the assumption of a fixed XCO.”
A UNIVERSAL, LOCAL STAR FORMATION LAW IN GALACTIC CLOUDS, NEARBY GALAXIES, HIGH-REDSHIFT DISKS, AND STARBURSTS (2011, unknown): “…of star-forming molecular clouds in nearby galaxies show no systematic variation with galactic properties (Bolatto et al. 2008; Fukui & Kawamura 2010) (although there is some preliminary evidence that the GMCmass function might vary from galaxy to galaxy – Rosolowsky 2005; Wong et al. 2011).”
Molecular Clouds in the Milky Way (2015, methodology): “…when applied to real data, the Larson relationships are not so readily produced by these analyses, as the dynamic range of clump size is typically less than 10 and the scatter of properties is large (Carr 1987, Stutzki & Guesten 1990, Simon et al. 2001, Schneider & Brooks 2004, Wong et al. 2011).”
THE PdBI ARCSECOND WHIRLPOOL SURVEY (PAWS): ENVIRONMENTAL DEPENDENCE OF GIANT MOLECULAR CLOUD PROPERTIES IN M51 (2014, methodology): “…sufficient resolution to identify individual GMCs (e.g., Fukui et al. 2001; Engargiola et al. 2003; Fukui 2005; Leroy et al. 2006; Mizuno et al. 2006; Rosolowsky 2007; Hughes et al. 2010; Wong et al. 2011; Hirota et al. 2011; Gratier et al. 2012; Rebolledo et al. 2012; Donovan Meyer et al. 2013).”
Cloud-scale Molecular Gas Properties in 15 Nearby Galaxies (2018, background): “…dispersion balancing their self-gravity, has been observed for clouds in the Milky Way disk (Heyer et al. 2009), the Large Magellanic Cloud (LMC; Wong et al. 2011), nearby dwarf galaxies (Bolatto et al. 2008), spiral galaxies (Donovan Meyer et al. 2013; Colombo et al. 2014a), starbursts…”
MOLECULAR GAS AND STAR FORMATION IN NEARBY DISK GALAXIES (2013, methodology): “…e.g., studies of the Milky Way ring by Heyer et al. (2009), the disk of NGC 6946 (Rebolledo et al. 2012), the LMC (Fukui et al. 2008; Hughes et al. 2010; Wong et al. 2011), or a sample of Local Group galaxies (Bolatto et al. 2008) all find typical GMC surface densities Σ ∼ 50– 100 M⊙ pc −2.”
Planck 2015 results - XXVIII. The Planck Catalogue of Galactic cold clumps (2015, unknown): “6 resolution for CO emission in the LMC (Fukui et al. 2008), while 27 sources are located inside the region observed by the higher resolution (45 ) MAGMA LMC survey (Wong et al. 2011).”
Star Formation in the Milky Way and Nearby Galaxies (2012, background): “Evidence for a higher value of αcloud has been found for the LMC (Fukui et al. 2001; Wong et al. 2011) and M33 (Engargiola et al. 2003; Rosolowsky 2005).”
The Formation and Destruction of Molecular Clouds and Galactic Star Formation (2015, background): “This tendency is actually observed in Milky Way outer disk, LMC, M33, and M51 (Rosolowsky 2005; Wong et al. 2011; Gratier et al. 2012; Hughes et al. 2010; Colombo et al. 2014) .”