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Related papers: Nonresonant Grain Acceleration in MHD Turbulence

200 papers

We discuss the physics of stochastic particle acceleration in relativistic magnetohydrodynamic (MHD) turbulence, combining numerical simulations of test-particle acceleration in synthetic wave turbulence spectra with detailed analytical…

High Energy Astrophysical Phenomena · Physics 2020-07-06 Camilia Demidem , Martin Lemoine , Fabien Casse

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

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

Turbulence can significantly accelerate the growth of dust grains by accretion of molecules. For dust dynamically coupled to the gas, the growth rate scales with the square of the Mach number, which means that the growth timescale can…

Astrophysics of Galaxies · Physics 2020-01-08 Lars Mattsson

Nonresonant current instability was identified by Bell (2004) as an important mechanism for magnetic field amplification in supernova remnants. In this paper we focus on studying the nonlinear stage of this instability using the…

Astrophysics of Galaxies · Physics 2014-06-06 Andrey Beresnyak , Hui Li

We study the drag force on dust grains moving at relativistic velocities through interstellar gas and explore its application. First, we derive a new analytical formula of the drag force at high energies and find that it is significantly…

Astrophysics of Galaxies · Physics 2017-10-04 Thiem Hoang

We study the linear growth and nonlinear saturation of the "acoustic Resonant Drag Instability" (RDI) when the dust grains, which drive the instability, have a wide, continuous spectrum of different sizes. This physics is generally…

Astrophysics of Galaxies · Physics 2021-12-13 Jonathan Squire , Stefania Moroianu , Philip F. Hopkins

We calculate and analyze the longevity of magnetohydrodynamic (MHD) wave modes that occur in the plane of a magnetic thin sheet. Initial turbulent conditions applied to a magnetically subcritical cloud are shown to lead to relatively rapid…

Astrophysics of Galaxies · Physics 2013-08-19 Shantanu Basu , Wolf B. Dapp

Intercluster medium is expected to be turbulent with turbulence being superAlfvenic at large scales. Magnetic fields substantially modify the turbulent cascade when the turbulence reaches the scales at which the fluctuation velocity gets…

Astrophysics · Physics 2009-11-11 A. Lazarian

Rapidly spinning magnetic grains can acquire large magnetic dipole moments due to the Barnett effect. Here we study the new effect of Barnett magnetic dipole-dipole interaction on grain-grain collisions and grain growth, assuming grains…

Astrophysics of Galaxies · Physics 2023-02-24 Thiem Hoang , Bao Truong

Collisionless, magnetized turbulence offers a promising framework for the generation of non-thermal high-energy particles in various astrophysical sites. Yet, the detailed mechanism that governs particle acceleration has remained subject to…

High Energy Astrophysical Phenomena · Physics 2022-08-17 Virginia Bresci , Martin Lemoine , Laurent Gremillet , Luca Comisso , Lorenzo Sironi , Camilia Demidem

The interaction between settling of dust grains and magnetorotational instability (MRI) turbulence in protoplanetary disks is analyzed. We use a reduced system of coupled ordinary differential equations to represent the interaction between…

Earth and Planetary Astrophysics · Physics 2015-06-04 Emmanuel Jacquet , Steven Balbus

Thermal dust polarization is a powerful tool to probe magnetic fields ($\textbf{B}$) and grain properties. However, a systematic study of the dependence of dust polarization on grain properties in protostellar environments is not yet…

Astrophysics of Galaxies · Physics 2024-03-14 Nguyen Chau Giang , Thiem Hoang

Aligned grains present a foreground for cosmic microwave emission studies. We review basic physical processes involved in grain alignment and discuss the niches for different alignment mechanisms. We show that mechanisms which were favored…

Astrophysics · Physics 2007-05-23 A. Lazarian , Jungyeon Cho

Given the important role turbulence plays in the settling and growth of dust grains in protoplanetary disks, it is crucial that we determine whether these disks are turbulent and to what extent. Protoplanetary disks are weakly ionized near…

Earth and Planetary Astrophysics · Physics 2024-04-12 David G. Rea , Jacob B. Simon , Daniel Carrera , Geoffroy Lesur , Wladimir Lyra , Debanjan Sengupta , Chao-Chin Yang , Andrew N. Youdin

We present a novel scenario for the growth of dust grains in galaxies at high-redshift ($z\sim 6$). In our model, the mechanical feedback from massive star clusters evolving within high-density pre-enriched media allows to pile-up a large…

Astrophysics of Galaxies · Physics 2021-09-02 Sergio Martínez-González , Sergiy Silich , Guillermo Tenorio-Tagle

The present paper reviews recent advances in the theory of nonlinear driven magnetohydrodynamic (MHD) waves in slow and Alfven resonant layers. Simple estimations show that in the vicinity of resonant positions the amplitude of variables…

Solar and Stellar Astrophysics · Physics 2015-05-20 Istvan Ballai , Michael Ruderman

Grain growth by accretion of gas-phase metals is a common assumption in models of dust evolution, but in dense gas, where the timescale is short enough for accretion to be effective, material is accreted in the form of ice mantles rather…

Astrophysics of Galaxies · Physics 2021-01-20 F. D. Priestley , I. De Looze , M. J. Barlow

Alignment of dust grains in astrophysical environments results in the polarization of starlight as well as the polarization of radiation emitted by dust. We demonstrate the advances in grain alignment theory allow the use of linear and…

Astrophysics of Galaxies · Physics 2019-10-02 A Lazarian , Thiem Hoang

Recent observations indicate that mm/cm-sized grains may exist in the embedded protostellar disks. How such large grains grow from the micron size (or less) in the earliest phase of star formation remains relatively unexplored. In this…

Earth and Planetary Astrophysics · Physics 2022-07-29 Yisheng Tu , Zhi-Yun Li , Ka Ho Lam