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Related papers: Quantitative Theory of Grain Alignment: Probing Gr…

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The dependence of polarization fraction $p$ on total intensity $I$ in polarized submillimeter emission measurements is typically parameterized as $p\propto I^{-\alpha}$ $(\alpha \leq 1)$, and used to infer dust grain alignment efficiency in…

Charging of dust grains in low-pressure plasmas is reviewed critically. A theory based on the Fokker-Planck equation and orbital motion limited approximation is proposed. The theory predicts that dust grains can acquire a positive charge in…

Plasma Physics · Physics 2013-07-09 S. N. Abolmasov , E. V. Romashchenko , P. Roca i Cabarrocas

The characterization of magnetic fields within molecular clouds is fundamental to understanding star formation processes. Accurately gauging the three-dimensional structure of these fields presents a challenge, as observational techniques…

Astrophysics of Galaxies · Physics 2024-11-18 Brandon Shane , Blakesley Burkhart , Laura Fissel , Susan E. Clark , Philip Mocz , Michael M. Foley

Thermal dust is the major polarized foreground hindering the detection of primordial cosmic microwave background (CMB) B-modes. Its signal exhibits complex behavior in frequency space, arising from the combined variation in our Galaxy of…

Focussing on preplanetary grains growth, we discuss the properties of dust aggregation driven by magnetic dipole forces. While there is no direct evidence for the existence of magnetic grains present in the solar nebula, there are reasons…

Astrophysics · Physics 2009-11-07 C. Dominik , H. Nuebold

The properties of interstellar grains can now be defined by a rapidly growing wealth of observational data. We rely upon models to combine these data with unobserved properties such as the size distribution of grains, their structure and…

Astrophysics · Physics 2007-05-23 Adolf N. Witt

A detailed study of interstellar polarization efficiency toward molecular clouds is used to attempt discrimination between grain alignment mechanisms in dense regions of the ISM. Background field stars are used to probe polarization…

Astrophysics · Physics 2008-11-26 D. C. B. Whittet , J. H. Hough , A. Lazarian , Thiem Hoang

Interstellar medium is turbulent and this induces relative motions of dust grains. We calculate relative velocities of charged grains in a partially ionized magnetized gas. We account for anisotropy of magnetohydrodynamic (MHD) turbulence,…

Astrophysics · Physics 2009-11-07 A. Lazarian , Huirong Yan

We review major progress on the modeling of electric dipole emission from rapidly spinning tiny dust grains, including polycyclic aromatic hydrocarbons (PAHs). We begin by summarizing the original model of spinning dust proposed by Draine…

Astrophysics of Galaxies · Physics 2015-06-12 Thiem Hoang , A. Lazarian

This paper gives a short summary of a mechanism of the enhanced paramagnetic relaxation that acts on rapidly rotating interstellar grains. We show that the Barnett magnetization that arises from grain rotation ensures that paramagnetic…

Astrophysics · Physics 2007-05-23 Lazarian A

Investigating the dust grain size and its dependence on substructures in protoplanetary disks is a crucial step in understanding the initial process of planet formation. Spectral indices derived from millimeter observations are used as a…

Earth and Planetary Astrophysics · Physics 2024-10-08 Dafa Li , Yao Liu , Hongchi Wang , Min Fang , Lei Wang

Magnetic fields are widely observed in various astronomical contexts, yet much remains unknown about their significance across different systems and cosmic epochs. Our current knowledge of the evolution of magnetic fields is limited by…

Astrophysics of Galaxies · Physics 2024-12-04 Jianhang Chen , Enrique Lopez-Rodriguez , R. J. Ivison , James E. Geach , Simon Dye , Xiaohui Liu , George Bendo

We present 870 $\mu$m ALMA polarization observation toward the Class I\hspace{-.1em}I protoplanetary disk around AS 209, which has concentric, multiple gaps and rings. We successfully detect the polarized emission and find that the…

Earth and Planetary Astrophysics · Physics 2019-09-25 Tomohiro Mori , Akimasa Kataoka , Satoshi Ohashi , Munetake Momose , Takayuki Muto , Hiroshi Nagai , Takashi Tsukagoshi

Spatially resolved (sub)millimeter polarization has been detected by ALMA in an increasing number of disks around young stellar objects. The majority of the observations show polarization patterns that are consistent with self-scattering,…

Solar and Stellar Astrophysics · Physics 2019-09-19 Haifeng Yang , Zhi-Yun Li

We recently questioned the treatment of a dust particle as a perfect absorber for electrons and ions and proposed a surface model for the charge of a dust particle in a quiescent plasma which combines the microscopic physics at the grain…

Plasma Physics · Physics 2009-08-24 Franz X. Bronold , H. Fehske , H. Kersten , H. Deutsch

Polarized extinction and emission from dust in the interstellar medium (ISM) are hard to interpret, as they have a complex dependence on dust optical properties, grain alignment and magnetic field orientation. This is particularly true in…

Astrophysics of Galaxies · Physics 2017-05-24 Lapo Fanciullo , Vincent Guillet , François Boulanger , Anthony Jones

The presence of charged dust grains is known to have a profound impact on the physical evolution of the multiphase interstellar medium (ISM). Despite its importance, this process is still poorly explored in numerical simulations due to its…

Astrophysics of Galaxies · Physics 2021-12-01 Martin Glatzle , Luca Graziani , Benedetta Ciardi

Observations of protoplanetary disks (PPDs) at sub-mm wavelengths suggest that polarisation is caused by scattering of thermal radiation. Most of the dust models that are used to explain these observations have major drawbacks: They either…

Solar and Stellar Astrophysics · Physics 2021-04-21 Robert Brunngräber , Sebastian Wolf

The properties of polarization in scattered light by aligned ellipsoidal grains are investigated with the Fredholm integral equation method (FIM) and the T-matrix method (Tmat), and the results are applied to the observed circular…

Astrophysics of Galaxies · Physics 2010-01-15 Masafumi Matsumura , Pierre Bastien

We study the rotational and translational kinetics of massive particulates (dust grains) absorbing the ambient gas. Equations for microscopic phase densities are deduced resulting in the Fokker-Planck equation for the dust component. It is…

Plasma Physics · Physics 2019-08-17 A. M. Ignatov , S. A. Trigger , S. A. Maiorov , W. Ebeling