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Related papers: Evaluating the Magnetic Field Strength in Molecula…

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The currently most viable methods to estimate magnetic field strengths in molecular cloud cores are Zeeman measurements and the Chandrasekhar-Fermi (CF) method. The CF-method estimates magnetic field strengths from polarimetry and relies on…

Astrophysics · Physics 2007-05-23 F. Heitsch , P. S. Li

We describe a method for determining the dispersion of magnetic field vectors about large-scale fields in turbulent molecular clouds. The method is designed to avoid inaccurate estimates of magnetohydrodynamic or turbulent dispersion - and…

The dynamical state of star-forming molecular clouds cannot be understood without determining the structure and strength of their magnetic fields. Measurements of polarized far-infrared radiation from thermally aligned dust grains are used…

Astrophysics · Physics 2009-11-06 F. Heitsch , E. G. Zweibel , M. -M. Mac Low , P. S. Li , M. L. Norman

The Davis-Chandrasekhar-Fermi (DCF) method provides an indirect way to estimate the magnetic field strength from statistics of magnetic field orientations. We compile all the previous DCF estimations from polarized dust emission…

Astrophysics of Galaxies · Physics 2022-02-02 Junhao Liu , Keping Qiu , Qizhou Zhang

The Davis-Chandrasekhar-Fermi (DCF) method is widely employed to estimate the mean magnetic field strength in astrophysical plasmas. In this study, we present a numerical investigation using the DCF method in conjunction with a promising…

Instrumentation and Methods for Astrophysics · Physics 2023-05-10 Parth Pavaskar , Huirong Yan , Jungyeon Cho

The magnetic field strength in molecular clouds is a fundamental quantity for theories of star formation. It is estimated by Zeeman splitting measurements in a few dense molecular cores, but its volume--averaged value within large molecular…

Astrophysics · Physics 2009-11-10 Paolo Padoan , Raul Jimenez , Mika Juvela , Aake Nordlund

The Davis-Chandrasekhar-Fermi (DCF) method is widely used to evaluate magnetic fields in star-forming regions. Yet it remains unclear how well DCF equations estimate the mean plane-of-the-sky field strength in a map region. To address this…

Astrophysics of Galaxies · Physics 2023-12-18 Philip C. Myers , Ian W. Stephens , Simon Coudé

We present the results of an extensive Arecibo observational survey of magnetic field strengths in the inter-core regions of molecular clouds to determine their role in the evolution and collapse of molecular clouds as a whole. Sensitive 18…

Astrophysics of Galaxies · Physics 2019-10-16 K. L. Thompson , T. H. Troland , C. Heiles

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

Dust polarization orientations in molecular clouds often tend to be close to tangential to the Stokes $I$ dust continuum emission contours. The magnetic field and the emission gradient orientations, therefore, show some correlation. A…

Astrophysics of Galaxies · Physics 2015-06-03 Patrick M. Koch , Ya-Wen Tang , Paul T. P. Ho

The mean plane-of-sky magnetic field strength is traditionally obtained from the combination of polarization and spectroscopic data using the Davis-Chandrasekhar-Fermi (DCF) technique. However, we identify the major problem of the DCF to be…

Astrophysics of Galaxies · Physics 2022-08-31 A. Lazarian , Ka Ho Yuen , Dmitri Pogosyan

Recent studies of the diffuse parts of molecular clouds have revealed the presence of parallel, ordered low-density filaments termed striations. Flows along magnetic field lines, Kelvin-Helmholtz instabilities and hydromagnetic waves are…

Astrophysics of Galaxies · Physics 2018-10-17 Aris Tritsis , Christoph Federrath , Nicola Schneider , Konstantinos Tassis

Despite the rich observational results on interstellar magnetic fields in star-forming regions, it is still unclear how dynamically significant the magnetic fields are at varying physical scales, because direct measurement of the field…

We expand our study on the dispersion of polarization angles in molecular clouds. We show how the effect of signal integration through the thickness of the cloud as well as across the area subtended by the telescope beam inherent to dust…

Astrophysics of Galaxies · Physics 2014-11-20 Martin Houde , John E. Vaillancourt , Roger H. Hildebrand , Shadi Chitsazzadeh , Larry Kirby

The Davis-Chandrasekhar-Fermi (DCF) method is widely used to indirectly estimate the magnetic field strength from the plane-of-sky field orientation. In this work, we present a set of 3D MHD simulations and synthetic polarization images…

Astrophysics of Galaxies · Physics 2021-10-04 Junhao Liu , Qizhou Zhang , Benoit Commercon , Valeska Valdivia , Anaelle Maury , Keping Qiu

Far-infrared (FIR) dust polarimetry enables the study of interstellar magnetic fields via tracing of the polarized emission from dust grains that are partially aligned with the direction of the field. The advent of high quality polarimetric…

We present the first resolved map of plane-of-sky magnetic field strength for a quiescent molecular cloud. GRSMC 45.60+0.30 subtends 40 x 10 pc at a distance of 1.88 kpc, masses 16,000 M_sun, and exhibits no star formation. Near-infrared…

Astrophysics of Galaxies · Physics 2012-08-31 Robert C. Marchwinski , Michael D. Pavel , Dan P. Clemens

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

Magnetic fields pervade in the interstellar medium (ISM) and are believed to be important in the process of star formation, yet probing magnetic fields in star formation regions is challenging. We propose a new method to use Faraday…

Astrophysics of Galaxies · Physics 2018-06-27 M. Tahani , R. Plume , J. C. Brown , J. Kainulainen

We estimate the polarized thermal dust emission from MHD simulations of protostellar collapse and outflow formation in order to investigate alignment of outflows with magnetic fields. The polarization maps indicate that alignment of an…

Astrophysics · Physics 2009-11-13 Tomoaki Matsumoto , Takeshi Nakazato , Kohji Tomisaka
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