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Related papers: Alignment of Dust in Molecular Clouds

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The origin of polarized emission from protoplanetary disks is uncertain. Three mechanisms have been proposed for such polarized emission: grain alignment with magnetic fields, grain alignment with radiation gradients, and self-scattering of…

We present an analysis of the relationship between the orientation of magnetic fields and filaments that form in 3D magnetohydrodynamic simulations of cluster-forming, turbulent molecular cloud clumps. We examine simulated cloud clumps with…

Astrophysics of Galaxies · Physics 2016-12-21 Mikhail Klassen , Ralph E. Pudritz , Helen Kirk

Polarized microwave emission from dust is an important foreground that may contaminate polarized CMB studies unless carefully accounted for. We discuss potential difficulties associated with this foreground, namely, the existence of…

Astrophysics · Physics 2015-06-24 A. Lazarian , D. Finkbeiner

This article reviews the current status of theoretical modeling of electric dipole radiation from spinning dust grains. The fundamentally simple problem of dust grain rotation appeals to a rich set of concepts of classical and quantum…

Astrophysics of Galaxies · Physics 2015-08-21 Yacine Ali-Haïmoud

Since the classical work by Purcell (1979) it has been generally accepted that most interstellar grains rotate suprathermally. Suprathermally rotating grains would be nearly perfectly aligned with the magnetic field by paramagnetic…

Astrophysics · Physics 2009-10-31 A. Lazarian , B. Draine

We present high resolution ($1024^3$) simulations of super-/hyper-sonic isothermal hydrodynamic turbulence inside an interstellar molecular cloud (resolving scales of typically 20 -- 100 AU), including a multi-disperse population of dust…

Astrophysics of Galaxies · Physics 2018-12-19 Lars Mattsson , Akshay Bhatnagar , Fred A. Gent , Beatriz Villarroel

Instruments achieve sharper and finer observations of micron-in-size dust grains in the top layers of young stellar discs. To provide accurate models, we revisit the theory of dust settling for small grains, when gas stratification, dust…

Earth and Planetary Astrophysics · Physics 2020-05-13 Guillaume Laibe , Charles-Edouard Brehier , Maxime Lombart

Recent observational progress has challenged the dust grain-alignment theories used to explain the polarized dust emission routinely observed in star-forming cores. In an effort to improve our understanding of the dust grain alignment…

The path to understanding star formation processes begins with the study of the formation of molecular clouds. The outskirts of these clouds are characterized by low column densities that allow the penetration of ultraviolet radiation,…

Astrophysics of Galaxies · Physics 2021-02-24 L. Beitia-Antero , A. I. Gómez de Castro , J. C. Vallejo

Polarized (sub)millimeter emission from dust grains in circumstellar disks was initially thought to be due to grains aligned with the magnetic field. However, higher resolution multi-wavelength observations along with improved models found…

The investigation of polarized light of protoplanetary disks is key for constraining the dust properties, disk morphology and embedded magnetic fields. However, different polarization mechanisms and the diversity of dust grain shapes and…

Solar and Stellar Astrophysics · Physics 2019-07-17 Robert Brunngräber , Sebastian Wolf

This paper provides a quantitative account of a recently introduced mechanism of mechanical alignment of suprathermally rotating grains. These rapidly rotating grains are essentially not susceptible to random torques arising from gas-grain…

Astrophysics · Physics 2009-10-28 Alex Lazarian , Michael Efroimsky

The orientations of filamentary molecular clouds in the Gould Belt and their local ICM (inter-cloud media) magnetic fields are studied using near-infrared dust extinction maps and optical stellar polarimetry data. These filamentary clouds…

Astrophysics of Galaxies · Physics 2015-06-17 Hua-bai Li , Min Fang , Thomas Henning , Jouni Kainulainen

In diffuse molecular clouds, possible precursors of star-forming clouds, the effect of the magnetic field is unclear. In this work we compare the orientations of filamentary structures in the Polaris Flare, as seen through dust emission by…

Astrophysics of Galaxies · Physics 2016-08-24 G. V. Panopoulou , I. Psaradaki , K. Tassis

The optical and near-infrared (OIR) polarization of starlight is typically understood to arise from the dichroic extinction of that light by dust grains whose axes are aligned with respect to a local magnetic-field. The size distribution of…

The Zeeman effect and dust grain alignment are two major methods for probing magnetic fields (B-fields) in molecular clouds, largely motivated by the study of star formation, as the B-field may regulate gravitational contraction and channel…

Astrophysics of Galaxies · Physics 2021-06-16 Hua-bai Li

Polarized dust continuum emission has been observed with ALMA in an increasing number of deeply embedded protostellar systems. It generally shows a sharp transition going from the protostellar envelope to the disk scale, with the…

Astrophysics of Galaxies · Physics 2021-08-04 Ka Ho Lam , Che-Yu Chen , Zhi-Yun Li , Haifeng Yang , Erin G. Cox , Leslie W. Looney , Ian Stephens

The degree of porosity in interstellar dust-grain material is poorly defined, although recent work has suggested that the grains could be highly porous. Aside from influencing the optical properties of the dust, porosity has the potential…

Astrophysics of Galaxies · Physics 2021-04-28 Drew A. Christianson , Robin T. Garrod

We study the behavior of large dust grains in turbulent molecular clouds (MCs). In primarily neutral regions, dust grains move as aerodynamic particles, not necessarily with the gas. We therefore directly simulate, for the first time, the…

Astrophysics of Galaxies · Physics 2016-11-09 Philip F. Hopkins , Hyunseok Lee

Context. Anomalous microwave emission (AME) is a component of interstellar medium emission peaking at 10-60 GHz. Its polarization is both a CMB foreground and a probe of the alignment physics of very small dust grains. Aims. We quantify…

Astrophysics of Galaxies · Physics 2026-04-30 Boy Lankhaar
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