English
Related papers

Related papers: Polarization Structure of Filamentary Clouds

200 papers

We have constructed two types of analytical models for an isothermal filamentary cloud supported mainly by magnetic tension. The first one describes an isolated cloud while the second considers filamentary clouds spaced periodically. Both…

Astrophysics of Galaxies · Physics 2015-06-23 Tomoyuki Hanawa , Kohji Tomisaka

Maps of polarized dust emission of molecular clouds reveal the morphology of the magnetic field associated with star-forming regions. In particular, polarization maps of hub-filament systems show the distortion of magnetic field lines…

Astrophysics of Galaxies · Physics 2024-05-21 Domitilla Tapinassi , Daniele Galli , Marco Padovani , Henrik Beuther

In this study, we perform 3D magnetohydrodynamics (MHD) simulations of filamentary molecular clouds. We then generate synthetic observations based on the simulation results. Using these, we investigate how the new polarization data analysis…

Astrophysics of Galaxies · Physics 2024-12-19 Haruka Fukihara , Daisuke Takaishi , Yoshiaki Misugi , Megumi Sasaki , Yusuke Tsukamoto

We examine the linear stability of an isothermal filamentary cloud permeated by a perpendicular magnetic field. Our model cloud is assumed to be supported by gas pressure against the self-gravity in the unperturbed state. For simplicity,…

Astrophysics of Galaxies · Physics 2017-10-11 Tomoyuki Hanawa , Takahiro Kudoh , Kohji Tomisaka

A recently discovered filament of polarized starlight that traces a coherent magnetic field is shown to have several properties that are consistent with an origin in the outer heliosheath of the heliosphere: (1) The magnetic field that…

The G14.225-0.506 infrared dark cloud (IRDC G14.2) displays a remarkable complex of parallel dense molecular filaments projected on the plane of the sky. Previous dust emission and molecular-line studies have speculated whether magnetic…

Astrophysics of Galaxies · Physics 2017-02-15 Fabio P. Santos , Gemma Busquet , Gabriel A. P. Franco , Josep M. Girart , Qizhou Zhang

We develop a theory for filamentary molecular clouds including the effects of ordered magnetic fields, and external pressure. We first derive a form of the virial equation appropriate for filamentary clouds. By comparing with observational…

Astrophysics · Physics 2007-05-23 Jason D. Fiege , Ralph E. Pudritz

This study is motivated by recent observations on ubiquitous interstellar density filaments and guided by modern theories of compressible magnetohydrodynamic (MHD) turbulence. The interstellar turbulence shapes the observed density…

Astrophysics of Galaxies · Physics 2019-08-07 Siyao Xu , Suoqing Ji , A. Lazarian

Filamentary structures are recognized as a fundamental component of interstellar molecular clouds in observations by the Herschel satellite. These filaments, especially massive filaments, often extend in a direction perpendicular to the…

Astrophysics of Galaxies · Physics 2021-06-04 Raiga Kashiwagi , Kohji Tomisaka

Filamentary molecular clouds are regarded as the place where newborn stars are formed. In particular, a hub region, a place where it appears as if several filaments are colliding, often indicates active star formation. To understand the…

Astrophysics of Galaxies · Physics 2023-09-06 Raiga Kashiwagi , Kazunari Iwasaki , Kohji Tomisaka

Several sets of data show that small interstellar grains captured in interstellar magnetic fields draped over the heliosphere appear to polarize the light of nearby stars. The maximum polarization direction is offset in ecliptic longitude…

Astrophysics · Physics 2007-05-23 Priscilla C. Frisch

Calculations are performed for the linear polarization of starlight due to extinction by aligned dust grains when the starlight traverses a medium with irregular magnetic fields. This medium is intended to represent the optically thick…

Astrophysics · Physics 2009-10-31 D. S. Wiebe , W. D. Watson

A model of magnetic field structure is presented to help test the prevalence of flux freezing in star-forming clouds of various shapes, orientations, and degrees of central concentration, and to estimate their magnetic field strength. The…

Astrophysics of Galaxies · Physics 2018-11-28 Philip C. Myers , Shantanu Basu , Sayantan Auddy

We present 850 $\mu$m polarization and $\rm C^{18}O (3-2)$ molecular line observations toward the X-shaped nebula in the California molecular cloud using the JCMT SCUBA-2/POL-2 and HARP instruments. The 850 $\mu$m emission shows that the…

Astrophysics of Galaxies · Physics 2023-07-12 Eun Jung Chung , Chang Won Lee , Woojin Kwon , Mario Tafalla , Shinyoung Kim , Archana Soam , Jungyeon Cho

Solar filament shape in projection on disc depends on the structure of the coronal magnetic field. We calculate the position of polarity inversion lines (PILs) of coronal potential magnetic field at different heights above the photosphere,…

Solar and Stellar Astrophysics · Physics 2015-11-18 Boris Filippov

We present first results from SIMPLIFI (Study of Interstellar Magnetic Polarization: a Legacy Investigation of Filaments), a SOFIA/HAWC+ $214~\mu\rm{}m$ polarimetric survey of Galactic molecular cloud filaments. We trace magnetic field…

We describe the results of a sequence of simulations of gravitational collapse in a turbulent magnetized region. The parameters are chosen to be representative of molecular cloud material. We find that several protostellar cores and…

Astrophysics · Physics 2009-11-06 D. Balsara , D. Ward-Thompson , R. M. Crutcher

We use numerical simulations of turbulent cluster-forming regions to study the nature of dense filamentary structures in star formation. Using four hydrodynamic and magnetohydrodynamic simulations chosen to match observations, we identify…

Astrophysics of Galaxies · Physics 2015-06-23 Helen Kirk , Ralph Pudritz , Mikhail Klassen , Samantha Pillsworth

Filamentary structure is important for the ISM and star formation. Galactic distribution of filaments may regulate the star formation rate in the Milky Way. However, interstellar filaments are intrinsically complex, making it difficult to…

Astrophysics of Galaxies · Physics 2024-06-12 Ke Wang , Yifei Ge , Tapas Baug

The classical picture of a star-forming filament is a near-equilibrium structure, with collapse dependent on its gravitational criticality. Recent observations have complicated this picture, revealing filaments as a mess of apparently…

Astrophysics of Galaxies · Physics 2014-02-12 Nickolas Moeckel , Andreas Burkert