A Hunt for Massive Starless Cores

Abstract

We carry out an ALMA ${\mathrm{N}}_2{\mathrm{D}}^{+}$(3-2) and 1.3~mm continuum survey towards 32 high mass surface density regions in seven Infrared Dark Clouds with the aim of finding massive starless cores, which may be the initial conditions for the formation of massive stars. Cores showing strong ${\mathrm{N}}_2{\mathrm{D}}^{+}$(3-2) emission are expected to be highly deuterated and indicative of early, potentially pre-stellar stages of star formation. We also present maps of these regions in ancillary line tracers, including C${}^{18}$O(2-1), DCN(3-2) and DCO${}^{+}$(3-2). Over 100 ${\mathrm{N}}_2{\mathrm{D}}^{+}$ cores are identified with our newly developed core-finding algorithm based on connected structures in position-velocity space. The most massive core has $\sim 70M_{\odot }$ (potentially $\sim 170M_{\odot }$) and so may be representative of the initial conditions for massive star formation. The existence and dynamical properties of such cores constrain massive star formation theories. We measure the line widths and thus velocity dispersion of six of the cores with strongest ${\mathrm{N}}_2{\mathrm{D}}^{+}$(3-2) line emission, finding results that are generally consistent with virial equilibrium of pressure confined cores.

27 pages, 16 figures, 4 tables, accepted by ApJ, comments welcome

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Cited by in corpus (41)

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• Zooming in to Massive Star Birth
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• SiO emission as a probe of Cloud-Cloud Collisions in Infrared Dark Clouds
• Similar complex kinematics within two massive, filamentary infrared dark clouds
• Rotating filament in Orion B: Do cores inherit their angular momentum from their parent filament?
• Evidence of Core Growth in the Dragon Infrared Dark Cloud: A Path for Massive Star Formation
• An ALMA study of the massive molecular clump N159W-North in the Large Magellanic Cloud: A possible gas flow penetrating one of the most massive protocluster systems in the Local Group
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• Star Formation in a Strongly Magnetized Cloud
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• GMC Collisions As Triggers of Star Formation. IV. The Role of Ambipolar Diffusion
• The Seahorse Nebula: New views of the filamentary infrared dark cloud G304.74+01.32 from SABOCA, Herschel, and WISE
• Sulphur-Bearing and Complex Organic Molecules in an Infrared Cold Core
• Multiple outflows in the high-mass cluster forming region, G25.82-0.17
• Interaction between the Supernova Remnant W44 and the Infrared Dark Cloud G034.77-00.55: shock induced star formation?
• Fire from Ice - Massive Star Birth from Infrared Dark Clouds
• CO Depletion in Infrared Dark Clouds
• Singly- and doubly-deuterated formaldehyde in massive star-forming regions