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Related papers: Magnetic Fields in High-Mass Infrared Dark Clouds

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Magnetic fields are ubiquitously observed in the interstellar medium (ISM) of present-day star-forming galaxies with dynamically relevant energy densities. Using three-dimensional magneto-hydrodynamic (MHD) simulations of the supernova (SN)…

Magnetic fields play an important role for the formation of stars in both local and high-redshift galaxies. Recent studies of dynamo amplification in the first dark matter haloes suggest that significant magnetic fields were likely present…

Astrophysics of Galaxies · Physics 2020-07-08 Piyush Sharda , Christoph Federrath , Mark R. Krumholz

The magnetic field within a few hundred parsecs of the center of the Galaxy is an essential component of any description of that region. The field has several pronounced observational manifestations: 1) morphological structures such as…

Astrophysics · Physics 2007-05-23 Mark Morris

We present new NH3 (1,1), (2,2), and (4,4) observations from the Karl G. Jansky Very Large Array (VLA) compiled with work in the literature to explore the range of conditions observed in young, massive star-forming regions. To sample the…

Astrophysics of Galaxies · Physics 2015-06-19 Cara Battersby , Adam Ginsburg , John Bally , Steve Longmore , Miranda Dunham , Jeremy Darling

Star formation in molecular clouds is intimately linked to their internal mass distribution. We present an unprecedentedly detailed analysis of the column density structure of a high-mass, filamentary molecular cloud, namely IRDC…

Astrophysics of Galaxies · Physics 2015-06-16 J. Kainulainen , S. E. Ragan , T. Henning , A. Stutz

Recent high-angular-resolution (up to 0.7") dust polarization observations toward star forming regions are summarized. With the Sub-Millimeter Array, the emission from the dense structures is traced and resolved. The detected magnetic field…

Astrophysics of Galaxies · Physics 2012-02-22 Ya-Wen Tang , Patrick M. Koch , Paul T. P. Ho

Understanding mass, size, and surface mass density of giant molecular clouds (GMCs) in galaxies is key to insights into star formation processes. We analyze these in M33 using Herschel dust and archival IRAM 30m telescope data, compared to…

This book chapter reviews the current state of observations of magnetic fields in diffuse H I and in dense molecular clouds. It covers techniques for measuring magnetic fields, the analysis of the observations, and the role of magnetic…

Astrophysics · Physics 2022-09-21 Carl Heiles , Richard Crutcher

High-mass star forming regions are typically thought to be dominated by supersonic motions. We present combined Very Large Array and Green Bank Telescope (VLA+GBT) observations of NH$_3$ (1,1) and (2,2) in the infrared dark cloud (IRDC)…

The IC5146 cloud is a nearby star-forming region in Cygnus, consisting of molecular gas filaments in a variety of evolutionary stages. We used optical and near-infrared polarization data toward the IC5146 cloud, reported in the first paper…

Astrophysics of Galaxies · Physics 2019-11-27 Jia-Wei Wang , Shih-Ping Lai , Dan P. Clemens , Patrick M. Koch , C. Eswaraiah , Wen-Ping Chen , A. K. Pandey

The magnetic field is a key ingredient in the recipe of star formation. Over the past two decades, millimeter and submillimeter interferometers have made major strides in unveiling the role of the magnetic field in star formation at…

Solar and Stellar Astrophysics · Physics 2019-03-11 Charles L. H. Hull , Qizhou Zhang

We present the SOFIA/HAWC+ 214 $\mu$m polarimetric observations toward the infrared dark cloud G351.77-0.53 (hereafter G351), complemented by existing multi-wavelength data sets. Infrared excess from the embedded sources indicate ongoing…

The origin and growth of magnetic fields in galaxies is still something of an enigma. It is generally assumed that seed fields are amplified over time through the dynamo effect, but there are few constraints on the timescale. It has…

Stars form in highly-magnetised, supersonic turbulent molecular clouds. Many of the tools and models that we use to carry out star formation studies rely upon the assumption of cloud isotropy. However, structures like high-density filaments…

Astrophysics of Galaxies · Physics 2020-01-08 James R. Beattie , Christoph Federrath

Infrared Dark Clouds (IRDCs), condensed regions of the ISM with high column densities, low temperatures and high masses, are suspected sites of star formation. Thousands of IRDCs have already been identified. To date, it has not been…

Astrophysics · Physics 2008-11-18 Matthijs H. D. van der Wiel , Russell F. Shipman

Star formation is essential in galaxy evolution and the cycling of matter. The support of interstellar clouds against gravitational collapse by magnetic (B-) fields has been proposed to explain the low observed star formation efficiency in…

We have comprehensively studied the multi-scale physical properties of the infrared dark cloud (IRDC) G28.34 (the Dragon cloud) with dust polarization and molecular line data from Planck, FCRAO-14m, JCMT, and ALMA. We find that the averaged…

Stars primarily form in galactic spiral arms within dense, filamentary molecular clouds. The largest and most elongated of these molecular clouds are referred to as ``bones," which are massive, velocity-coherent filaments (lengths ~20 to…

Atomic gas in the diffuse interstellar medium (ISM) is organized in filamentary structures. These structures usually host cold and dense molecular clumps. The Galactic magnetic field is considered to play an important role in the formation…

Astrophysics of Galaxies · Physics 2022-09-14 R. Skalidis , K. Tassis , G. V. Panopoulou , J. L. Pineda , Y. Gong , N. Mandarakas , D. Blinov , S. Kiehlmann , J. A. Kypriotakis

We present the B-fields mapped in IRDC G34.43+0.24 using 850\,$\mu$m polarized dust emission observed with the POL-2 instrument at JCMT. We examine the magnetic field geometries and strengths in the northern, central, and southern regions…