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Related papers: Grain Alignment in Molecular Clouds

200 papers

Dust polarization, which comes from the alignment of aspherical grains to magnetic fields, has been widely employed to study the interstellar medium (ISM) dust properties. The wavelength dependence of the degree of optical polarization,…

Astrophysics of Galaxies · Physics 2024-11-15 Raphael Skalidis

Recent observations of neutral Galactic interstellar medium showed that filamentary structures of HI clouds are aligned with the interstellar magnetic field. Many interesting applications are proposed based on the alignment such as…

Astrophysics of Galaxies · Physics 2016-12-14 Tsuyoshi Inoue , Shu-ichiro Inutsuka

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…

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

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

One of the key problems in star formation research is to determine the role of magnetic fields. Starting from the atomic inter-cloud medium (ICM) which has density nH ~ 1 per cubic cm, gas must accumulate from a volume several hundred pc…

Astrophysics of Galaxies · Physics 2015-05-13 Hua-bai Li , C. Darren Dowell , Alyssa Goodman , Roger Hildebrand , Giles Novak

Continuum polarization over the UV-to-microwave range is due to dichroic extinction (or emission) by asymmetric, aligned dust grains. Because of both grain alignment and scattering physics, the wavelength dependence of the polarization,…

Atacama Large Millimeter/Submillimeter Array (ALMA) has revolutionized the field of dust polarization in protoplanetary disks across multiple wavelengths. Previous observations and empirical modeling suggested multiple mechanisms of dust…

Solar and Stellar Astrophysics · Physics 2024-07-30 Nguyen Tat Thang , Pham Ngoc Diep , Thiem Hoang , Le Ngoc Tram , Nguyen Bich Ngoc , Nguyen Thi Phuong , Bao Truong

Dust polarization at (sub)millimeter wavelengths has been observed for many protoplanetary disks. Theoretically, multiple origins potentially contribute to the polarized emission but it is still uncertain what mechanism is dominant in disk…

Earth and Planetary Astrophysics · Physics 2021-03-03 Tomohiro Mori , Akimasa Kataoka

Within four nearby (d < 160 pc) molecular clouds, we statistically evaluate the structure of the interstellar magnetic field, projected on the plane of the sky and integrated along the line of sight, as inferred from the polarized thermal…

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

We study the physical processes inducing the alignment of the grain axis of maximum inertia moment with the angular momentum (${\bf J}$, i.e., internal alignment) and of ${\bf J}$ with the magnetic field (i.e., external alignment) of very…

Astrophysics of Galaxies · Physics 2022-11-30 Thiem Hoang , Le Ngoc Tram , Vo Hong Minh Phan , Nguyen Chau Giang , Nguyen Thi Phuong , Nguyen Duc Dieu

Recent observation of 850 micron sub-mm polarization from T Tauri disks opens up the possibility of studying magnetic field structure within protostellar disks. The degree of polarization is around 3 % and the direction of polarization is…

Solar and Stellar Astrophysics · Physics 2009-01-21 Jungyeon Cho , A. Lazarian

It is well known that aligned, aspherical dust grains emit polarized radiation and that the degree of polarization depends on the angle $\psi$ between the interstellar magnetic field and the line of sight. However, anisotropy of the dust…

Astrophysics of Galaxies · Physics 2020-01-08 Brandon S. Hensley , Cheng Zhang , James J. Bock

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 molecular cloud, DR21 Main, is an example of a large-scale gravitational collapse about an axis near the plane of the sky where the collapse is free of major disturbances due to rotation or other effects. Using flux maps, polarimetric…

Astrophysics · Physics 2011-02-11 Larry Kirby

Telescopes are now able to resolve dust polarization across circumstellar disks at multiple wavelengths, allowing the study of the polarization spectrum. Most disks show clear evidence of dust scattering through their unidirectional…

Solar and Stellar Astrophysics · Physics 2022-04-27 Zhe-Yu Daniel Lin , Zhi-Yun Li , Haifeng Yang , Ian Stephens , Leslie Looney , Rachel Harrison , Manuel Fernández-López

Polarized dust emission is a key tracer in the study of interstellar medium and of star formation. The observed polarization, however, is a product of magnetic field structure, dust grain properties and grain alignment efficiency, as well…

We investigate the combined effect of solar wind, Poynting-Robertson drag, and the frozen-in interplanetary magnetic field on the motion of charged dust grains in our solar system. For this reason we derive a secular theory of motion by the…

Earth and Planetary Astrophysics · Physics 2016-08-26 Christoph Lhotka , Philippe Bourdin , Yasuhito Narita

Grain microstructures are crucial to the mechanical properties, performance, and often lifetime of metallic components. Hence, the prediction of grain microstructures emerging from solidification processes at relevant macroscopic scale is…

Materials Science · Physics 2025-04-18 Salem Mosbah , Rodrigo Gómez Vázquez , Constantin Zenz , Damien Tourret , Andreas Otto