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Related papers: Dust-driven Dynamos in Accretion Disks

200 papers

Dust particles immersed in a plasma environment become charged through the collection of electrons and ions at random times, causing the dust charge to fluctuate about an equilibrium value. Small grains (with radii less than 1 \mum) or…

Plasma Physics · Physics 2018-05-16 Lorin S. Matthews , Babak Shotorban , Truell W. Hyde

The powerful narrow jets observed to emanate from many compact accreting objects may arise from the twisting of a magnetic field threading a differentially rotating accretion disk which acts to magnetically extract angular momentum and…

Astrophysics · Physics 2009-11-06 R. V. E. Lovelace , H. Li , G. V. Ustyugova , M. M. Romanova , S. A. Colgate

I discuss three mutually-supportive notions or assumptions regarding jets and accretion. The first is magnetocentrifugal acceleration (MCA), the overwhelmingly favored mechanism for the production of jets in most steady accreting systems.…

Solar and Stellar Astrophysics · Physics 2018-03-19 Peter Todd Williams

We calculate the evolution of a star-forming cloud core using a three-dimensional resistive magnetohydrodynamics simulation, treating dust grains as Lagrangian particles, to investigate the dust motion in the early star formation stage. We…

Solar and Stellar Astrophysics · Physics 2022-12-14 Shunta Koga , Masahiro N. Machida

We investigate the dynamics of the accretion disks of young stars with fossil large-scale magnetic field. The author's magnetohydrodynamic (MHD) model of the accretion disks is generalized to consider the dynamical influence of the magnetic…

Solar and Stellar Astrophysics · Physics 2022-12-28 Sergey A. Khaibrakhmanov , Alexander E. Dudorov

We present detailed models of irradiated T Tauri disks including dust grain growth with power-law size distributions. The models assume complete mixing between dust and gas and solve for the vertical disk structure…

Astrophysics · Physics 2009-11-06 Paola D'Alessio , Nuria Calvet , Lee Hartmann

We show that accretion disks with magnetic fields in them ought to make jets provided that their electrical conductivity prevents slippage and there is an ambient pressure in their surroundings. We study equilibria of highly wound magnetic…

Astrophysics · Physics 2009-11-07 D Lynden-Bell

Fast, collimated jets are ubiquitous features of young stellar objects (YSOs). They are generally thought to be powered by disk accretion, but the details are debated. Through 2D (axisymmetric) MHD simulations, we find that a fast…

Solar and Stellar Astrophysics · Physics 2025-06-05 Yisheng Tu , Zhi-Yun Li , Zhaohuan Zhu , Xiao Hu , Chun-Yen Hsu

Observations have shown that continuous radio emission and also sporadic H-alpha and X-ray emission are prominent in singular, low-mass objects later than spectral class M. These activity signatures are interpreted as being caused by…

Solar and Stellar Astrophysics · Physics 2015-05-28 Ch. Helling , M. Jardine , F. Mokler

The winds of cool luminous AGB stars are commonly assumed to be driven by radiative acceleration of dust grains which form in the extended atmospheres produced by pulsation-induced shock waves. The dust particles gain momentum by absorption…

Solar and Stellar Astrophysics · Physics 2015-05-28 Susanne Höfner

In this lecture I review the theory of magnetized accretion discs driving jets, with a focus on Young Stellar Objects (YSOs). I first introduce observational and theoretical arguments in favor of the ``disc wind'' paradigm. There, accretion…

Astrophysics · Physics 2007-05-23 Jonathan Ferreira

The polarisation of light induced by aligned interstellar dust serves as a significant tool in investigating cosmic magnetic fields, dust properties, and poses a challenge in characterising the polarisation of the cosmic microwave…

The significance of jets and accretion disks in Astrophysics may be growing far beyond any single example of recent finds in the scientific journals. This brief review will summarize recent, significant manifestations of accretion disk…

General Physics · Physics 2014-08-25 L. A. Morabito , D. Meyer

Recent research on the buildup of rocks from small dust grains has reaffirmed that grain growth in protoplanetary disks should occur quickly. Calculation of growth rates have been made for a variety of growth processes and generally predict…

Astrophysics · Physics 2007-05-23 Steven V. W. Beckwith , Thomas Henning , Yoshitsugu Nakagawa

We examine the radiatively driven mass accretion onto galactic nuclei due to the intensive radiation from circumnuclear starbursts. The radiation from a starburst not only contracts an inner gas disk by the radiation flux force, but also…

Astrophysics · Physics 2009-10-30 Masayuki Umemura , Jun Fukue , Shin Mineshige

We study the dynamics of large, charged dust grains in turbulent giant molecular clouds (GMCs). Massive dust grains behave as aerodynamic particles in primarily neutral dense gas, and thus are able to produce dramatic small-scale…

Astrophysics of Galaxies · Physics 2017-07-11 Hyunseok Lee , Philip F. Hopkins , Jonathan Squire

Context. Young Stellar Objects (YSOs) are observed to undergo powerful accretion events known as FU Orionis outbursts (FUors). Such events of episodic accretion are now considered to be common during low mass star formation, wherein the…

Solar and Stellar Astrophysics · Physics 2025-05-07 Kundan Kadam , Eduard Vorobyov , Peter Woitke , Manuel Güdel

From millimeter observations of classical T Tauri stars, it is suggested that dust grains in circumstellar disks have grown to millimeter size or larger. However, gas drag on such large grains induces rapid accretion of the dust. We examine…

Astrophysics · Physics 2009-11-10 Taku Takeuchi , D. N. C. Lin

This is a doctorate level lecture on the physics of accretion discs driving magnetically self-confined jets, usually referred to in the literature as disc winds. I will first review the governing magnetohydrodynamic equations and then…

Astrophysics · Physics 2008-11-26 Jonathan Ferreira