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Related papers: On the Disalignment of Interstellar Grains

200 papers

While the problem of grain alignment was posed more than 60 years ago the quantitative model of grain alignment that can account for the observed polarization arising from aligned grains has been formulated only recently. The quantitative…

Astrophysics of Galaxies · Physics 2009-03-09 A. Lazarian

Magnetic fields play a crucial role in various astrophysical processes, including star formation, accretion of matter, transport processes (e.g., transport of heat), and cosmic rays. One of the easiest ways to determine the magnetic field…

Astrophysics · Physics 2009-11-13 A. Lazarian

Most astrophysical systems, e.g. stellar winds, the diffuse interstellar medium, molecular clouds, are magnetized with magnetic fields that influence almost all of their properties. One of the most informative techniques of magnetic field…

Astrophysics · Physics 2009-11-07 A. Lazarian

Dust grains drift through the interstellar medium (ISM) and are aligned with the magnetic field. Here we study the effect of grain alignment and grain motion on grain growth in molecular clouds (MCs). We first discuss the characteristic…

Astrophysics of Galaxies · Physics 2022-04-06 Thiem Hoang

In the previous papers in this series, we found that radiative torques can play a major role in the alignment of grains with the interstellar magnetic field. Since the radiative torques can drive the grains to suprathermal rotational…

Astrophysics · Physics 2009-11-07 Joseph C. Weingartner , B. T. Draine

Motivated by a recent study by Lazarian and Draine, which showed that a high degree of grain alignment of the paramagnetic dust is achievable if the rates of internal relaxation are controlled by the Barnett relaxation process, we undertake…

Astrophysics · Physics 2009-10-31 A. Lazarian , M. Efroimsky

Paramagnetic alignment of non-spherical dust grains rotating at thermal velocities is studied. The analytical solution is found for the alignment measure of oblate grains. Perturbative approach is used for solving the problem. It is shown…

Astrophysics · Physics 2009-10-28 A. Lazarian

Paramagnetic alignment of thermally rotating oblate dust grains is studied analytically for finite ratios of grain to gas temperatures. For such ratios, the alignment of angular momentum J in respect to the grain axis of maximal inertia is…

Astrophysics · Physics 2015-06-24 A. Lazarian

Interstellar dust grains are non-spherical and, in some environments, partially aligned along the direction of the interstellar magnetic field. Numerous alignment theories have been proposed, all of which examine the grain rotational…

Astrophysics of Galaxies · Physics 2021-03-15 Joseph C. Weingartner , Erald Kolasi , Cameron Woods

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

We study the radial and vertical stability of dust grains launched with all charge-to-mass ratios at arbitrary distances from rotating planets with complex magnetic fields. We show that the aligned dipole magnetic field model analyzed by…

Earth and Planetary Astrophysics · Physics 2012-06-06 Daniel Jontof-Hutter , Douglas P. Hamilton

We study the stability of charged dust grains orbiting a planet and subject to gravity and the electromagnetic force. Our numerical models cover a broad range of launch distances from the planetary surface to beyond synchronous orbit, and…

Earth and Planetary Astrophysics · Physics 2012-01-18 Daniel Jontof-Hutter , Douglas P. Hamilton

Irregular dust grains are subject to radiative torques when irradiated by interstellar starlight. It is shown how these radiative torques may be calculated using the discrete dipole approximation. Calculations are carried out for one…

Astrophysics · Physics 2009-10-28 B. T. Draine , Joseph C. Weingartner

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

One of the most informative techniques of studying magnetic fields in molecular clouds is based on the use of starlight polarization and polarized emission arising from aligned dust. How reliable the interpretation of the polarization maps…

Astrophysics · Physics 2017-01-18 A. Lazarian

Thermal fluctuations in the magnetization of interstellar grains will produce magnetic dipole emission at frequencies below ~100 GHz. We show how to calculate absorption and emission from small particles composed of magnetic materials. The…

Astrophysics · Physics 2009-10-30 B. T. Draine , A. Lazarian

It is shown that mechanical alignment of grains can be efficient for grains rotating suprathermally, i.e. with kinetic energy substantially exceeding $k$ (the Boltzmann constant) over any temperature in the system. The paper studies…

Astrophysics · Physics 2009-10-28 A. Lazarian

Magnetic fields (B-fields) in galaxies have recently been traced using far-infrared and sub-mm polarimetric observations with SOFIA, JCMT, and ALMA. The main assumption is that dust grains are magnetically aligned with the local B-field in…

Astrophysics of Galaxies · Physics 2024-03-01 Enrique Lopez-Rodriguez , Le Ngoc Tram

The motion of diamagnetic dust particles in interstellar magnetic fields is studied numerically with several different sets of parameters. Two types of behavior are observed, depending on the value of the critical number $R$, which is a…

Astrophysics of Galaxies · Physics 2018-02-21 Renaud Papoular

Recent (sub)millimeter polarization observations of protoplanetary disks reveal toroidally aligned, effectively prolate dust grains large enough (at least ~100 $\mu$m) to efficiently scatter millimeter light. The alignment mechanism for…

Earth and Planetary Astrophysics · Physics 2025-10-02 Zhe-Yu Daniel Lin , Zhi-Yun Li , Haifeng Yang , Leslie W. Looney , Ian W. Stephens , Manuel Fernández-López , Rachel E. Harrison