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Related papers: Nonresonant Grain Acceleration in MHD Turbulence

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The diffusion of astrophysical magnetic fields in conducting fluids in the presence of turbulence depends on whether magnetic fields can change their topology via reconnection in highly conducting media. Recent progress in understanding…

Astrophysics of Galaxies · Physics 2012-12-17 R. Santos-Lima , A. Lazarian , E. M. de Gouveia Dal Pino , J. Cho

The aim of this paper is to study the vertical profile of small dust particles in protoplanetary discs in which angular momentum transport is due to MHD turbulence driven by the magnetorotational instability. We consider particle sizes that…

Earth and Planetary Astrophysics · Physics 2009-11-13 Sebastien Fromang , Richard P. Nelson

Fast Magnetic Reconnection is currently regarded as an important process also beyond the solar system, specially in magnetically dominated regions of galactic and extragalactic sources like the surrounds of black holes and relativistic…

Grain alignment theory suggests that grains should be aligned in circumstellar regions and the observational data available supports this conclusion. We discuss the alignment of grains via (1) magnetic relaxation, (2) mechanical processes,…

Astrophysics · Physics 2007-05-23 Lazarian A

Planet formation in the discs around young stars involves the coagulation of sub-micron sized dust grains into much larger grains that may be mixed by turbulence and migrate through the disc. In this paper, we describe how we have combined…

Earth and Planetary Astrophysics · Physics 2026-02-04 Matthew R. Bate , Mark A. Hutchison , Daniel Elsender

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

We argue that charged dust grains could significantly impact the confinement and transport of galactic cosmic rays. For sub-GeV to ~1000GeV cosmic rays, small-scale parallel Alfv\'en waves, which isotropize cosmic rays through gyro-resonant…

High Energy Astrophysical Phenomena · Physics 2021-02-03 Jonathan Squire , Philip F Hopkins , Eliot Quataert , Philipp Kempski

Turbulence in an incompressible fluid with and without a magnetic field as well as moderately compressible MHD turbulence are compared. For the magnetohydrodynamic (MHD) models the probability distribution functions of the velocity…

Astrophysics · Physics 2007-05-23 Nicholas Hall , G. Kowal , A. Lazarian , Jungyeon Cho

Turbulence is the most common state of astrophysical flows. In typical astrophysical fluids, turbulence is accompanied by strong magnetic fields, which has a large impact on the dynamics of the turbulent cascade. Recently, there has been a…

Astrophysics · Physics 2011-05-10 Jungyeon Cho , A. Lazarian , Ethan Vishniac

Dust is an essential component of the interstellar medium (ISM) and plays an important role in many different astrophysical processes and phenomena. Traditionally, dust grains are known to be destroyed by thermal sublimation, Coulomb…

Astrophysics of Galaxies · Physics 2020-07-07 Thiem Hoang

Clustering and dynamics of nano-sized particles (nano dust) is investigated using high-resolution ($1024^3$) simulations of compressible isothermal hydrodynamic turbulence, intended to mimic the conditions inside cold molecular clouds in…

Astrophysics of Galaxies · Physics 2018-11-27 Lars Mattsson

We investigate magnetohydrodynamic (MHD) turbulence in plane shear flows with a streamwise background magnetic field in the super-Alfv\'enic regime. We show that the large-scale velocity shear suppresses turbulence imbalance, driving the…

Space Physics · Physics 2026-02-17 M. Kavtaradze , G. Mamatsashvili , G. Chagelishvili , E. Uchava

Collisions of gas particles with a drifting grain give rise to a mechanical torque on the grain. Recent work by Lazarian & Hoang showed that mechanical torques might play a significant role in aligning helical grains along the interstellar…

Astrophysics of Galaxies · Physics 2016-02-16 Indrajit Das , Joseph C. Weingartner

Recent advances in understanding of magnetohydrodynamic (MHD) turbulence call for substantial revisions in our understanding of cosmic ray transport. In this paper we use gyroresonance recently obtained scaling laws for MHD modes to…

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

Weakly ionized protoplanetary disks (PPDs) are subject to non-ideal-magnetohydrodynamic (MHD) effects including Ohmic resistivity, the Hall effect and ambipolar diffusion (AD), and the resulting magnetic diffusivities ($\eta_O, \eta_H$ and…

Earth and Planetary Astrophysics · Physics 2016-03-16 Rui Xu , Xue-Ning Bai

Context: Aligned dust grains are commonly exploited to probe the magnetic field orientation. However, the exact physical processes that result in a coherent large-scale grain alignment are far from being constrained. Aims: In this work, we…

Astrophysics of Galaxies · Physics 2023-07-05 Stefan Reissl , Paul Meehan , Ralf S. Klessen

We investigate the dynamics of dust concentration in actively accreting, substructured, non-ideal MHD wind-launching disks using 2D and 3D simulations incorporating pressureless dust fluids of various grain sizes and their aerodynamic…

Earth and Planetary Astrophysics · Physics 2025-05-14 Chun-Yen Hsu , Zhi-Yun Li , Yisheng Tu , Xiao Hu , Min-Kai Lin

Instruments achieve sharper and finer observations of micron-in-size dust grains in the top layers of young stellar discs. To provide accurate models, we revisit the theory of dust settling for small grains, when gas stratification, dust…

Earth and Planetary Astrophysics · Physics 2020-05-13 Guillaume Laibe , Charles-Edouard Brehier , Maxime Lombart

MHD Turbulence is common in many space physics and astrophysics environments. We first discuss the properties of incompressible MHD turbulence. A well-conductive fluid amplifies initial magnetic fields in a process called small-scale…

Astrophysics of Galaxies · Physics 2015-06-19 Andrey Beresnyak , Alex Lazarian

This is the second in a series of papers on the effects of dust on multifluid, MHD shock waves in weakly ionized molecular gas. We investigate the influence of dust on the critical shock speed, v_crit, above which C shocks cease to exist.…

Astrophysics · Physics 2009-11-10 Glenn E. Ciolek , Wayne G. Roberge , Telemachos Ch. Mouschovias