A Virialized Filamentary Infrared Dark Cloud

Abstract

The initial conditions of massive star and star cluster formation are expected to be cold, dense and high column density regions of the interstellar medium, which can reveal themselves via near, mid and even far-infrared absorption as Infrared Dark Clouds (IRDCs). Elucidating the dynamical state of IRDCs thus constrains theoretical models of these complex processes. In particular, it is important to assess whether IRDCs have reached virial equilibrium, where the internal pressure balances that due to the self-gravitating weight of the cloud plus the pressure of the external environmental. We study this question for the filamentary IRDC G035.39-00.33 by deriving mass from combined NIR & MIR extinction maps and velocity dispersion from C18O (1-0) & (2-1) line emission. In contrast to our previous moderately super-virial results based on 13CO emission and MIR-only extinction mapping, with improved mass measurements we now find that the filament is consistent with being in virial equilibrium, at least in its central parsec-wide region where ~1000 M_Sun snakes along several parsecs. This equilibrium state does not require large-scale net support or confinement by magnetic fields.

4 pages, 2 figures, Accepted to ApJL

References in corpus (1)

• Mid-Infrared Extinction Mapping of Infrared Dark Clouds II. The Structure of Massive Starless Cores and Clumps

Cited by in corpus (31)

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• Resolving the fragmentation of high line-mass filaments with ALMA: the integral shaped filament in Orion A
• Complex, Quiescent Kinematics in a Highly Filamentary Infrared Dark Cloud
• Gravitational fragmentation caught in the act: the filamentary Musca molecular cloud
• Investigating the structure and fragmentation of a highly filamentary IRDC
• Gas Kinematics and Excitation in the Filamentary IRDC G035.39-00.33
• The Deuterium Fraction in Massive Starless Cores and Dynamical Implications
• SEDIGISM: The kinematics of ATLASGAL filaments
• Temperature structure and kinematics of the IRDC G035.39-00.33
• The Giant Molecular Cloud Environments of Infrared Dark Clouds
• Structure and Fragmentation of a high line-mass filament: Nessie
• Widespread deuteration across the IRDC G035.39-00.33
• Kiloparsec-Scale Simulations of Star Formation in Disk Galaxies. I. The unmagnetized and zero-feedback limit
• Physical Conditions of the Earliest Phases of Massive Star Formation: Single-Dish and Interferometric Observations of Ammonia and CCS in Infrared Dark Clouds
• Kiloparsec-Scale Simulations of Star Formation in Disk Galaxies III. Structure and Dynamics of Filaments and Clumps in Giant Molecular Clouds
• On the size of the CO-depletion radius in the IRDC G351.77-0.51
• The Inception of Star Cluster Formation Revealed by [CII] Emission Around an Infrared Dark Cloud
• Subsonic islands within a high-mass star-forming IRDC
• Similar complex kinematics within two massive, filamentary infrared dark clouds
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• Characterising the high-mass star forming filament G351.776--0.527 with Herschel and APEX dust continuum and gas observations
• G048.66-0.29: Physical State of an Isolated Site of Massive Star Formation
• Astrochemical modelling of infrared dark clouds
• Kinematic and Thermal Structure at the onset of high-mass star formation
• Structure, Dynamics and Deuterium Fractionation of Massive Pre-Stellar Cores
• Gas Kinematics of the Massive Protocluster G286.21+0.17 Revealed by ALMA
• Molecular Clouds: Internal Properties, Turbulence, Star Formation and Feedback
• The Seahorse Nebula: New views of the filamentary infrared dark cloud G304.74+01.32 from SABOCA, Herschel, and WISE
• CO Depletion in Infrared Dark Clouds