English
Related papers

Related papers: Kolmogorov Dissipation scales in Weakly Ionized Pl…

200 papers

The ohmic decay of magnetic fields in the crusts of neutron stars is generally believed to be governed by Hall drift which leads to what is known as a Hall cascade. Here we show that helical and fractionally helical magnetic fields undergo…

High Energy Astrophysical Phenomena · Physics 2020-09-18 Axel Brandenburg

The stratification-driven Hall instability in a weakly ionized polytropic plasma is investigated in the local approximation within an equilibrium Keplerian disk of a small aspect ratio. The leading order of the asymptotic expansions in the…

Astrophysics · Physics 2011-02-11 Yuri M. Shtemler , Michael Mond , Edward Liverts

We present a series of radiative MHD simulations addressing the origin and distribution of mixed polarity magnetic field in the solar photosphere. To this end we consider numerical simulations that cover the uppermost 2-6 Mm of the solar…

Solar and Stellar Astrophysics · Physics 2015-06-19 M. Rempel

Turbulence is ubiquitous in plasmas, leading to rich dynamics characterized by irregularity, irreversibility, energy fluctuations across many scales, and energy transfer across many scales. Another fundamental and generic feature of…

Plasma Physics · Physics 2017-02-14 Vladimir Zhdankin , Stanislav Boldyrev , Dmitri A. Uzdensky

A ray-theoretic phase space description of linear waves in a two-fluid (charges and neutrals) magnetized plasma is used to calculate analytic decay rates and mode transmission and conversion coefficients between fast and slow waves in two…

Solar and Stellar Astrophysics · Physics 2023-04-12 Paul S Cally , M. M. Gomez-Miguez

Small-scale dynamos play important roles in modern astrophysics, especially on Galactic and extragalactic scales. Owing to dynamo action, purely hydrodynamic Kolmogorov turbulence hardly exists and is often replaced by hydromagnetic…

Astrophysics of Galaxies · Physics 2022-12-20 A. Brandenburg , I. Rogachevskii , J. Schober

Polarizability tensor of a strongly magnetized plasma and the polarization vectors and opacities of normal electromagnetic waves are studied for the conditions typical of neutron star atmospheres, taking account of partial ionization…

Astrophysics · Physics 2009-11-10 A. Y. Potekhin , Dong Lai , G. Chabrier , W. C. G. Ho

When the ion mean free path much exceeds the Larmor radius in a plasma, the viscous stress tensor is altered dramatically, and depends only upon quantities measured along the field lines. This regime corresponds to typical interstellar…

Astrophysics · Physics 2009-11-10 Steven A. Balbus

The limitations of Hall MHD as a model for turbulence in weakly collisional plasmas are explored using quantitative comparisons to Vlasov-Maxwell kinetic theory over a wide range of parameter space. The validity of Hall MHD in the cold ion…

Solar and Stellar Astrophysics · Physics 2020-01-29 Gregory G. Howes

We present scaling laws for advection, radiation, magnetic drag and ohmic dissipation in the atmospheres of hot giant exoplanets. In the limit of weak thermal ionization, ohmic dissipation increases with the planetary equilibrium…

Earth and Planetary Astrophysics · Physics 2015-05-30 Kristen Menou

In this paper, we show a "proof of concept" of the heating mechanism of the solar chromosphere due to wave dissipation caused by the effects of partial ionization. Numerical modeling of non-linear wave propagation in a magnetic flux tube,…

Solar and Stellar Astrophysics · Physics 2016-03-16 S. Shelyag , E. Khomenko , A. de Vicente , D. Przybylski

The efficient release of magnetic energy in astrophysical plasmas, such as during solar flares, can in principle be achieved through magnetic diffusion, at a rate determined by the associated electric field. However, attempts at measuring…

This Chapter outlines the basic properties of waves in solar partially ionized plasmas. It provides a summary of the main sets of equations, from the single-fluid formalism, to the multi-fluid one, giving examples for purely hydrogen, and…

Solar and Stellar Astrophysics · Physics 2024-09-19 Elena Khomenko , David Martínez-Gómez

A simple collisional three-component plasma model consisting of electrons, ions, and neutrals with arbitrary collision frequencies and dynamic time scales is considered. It is shown that the usual MHD-approach dealing with magnetic field…

Solar and Stellar Astrophysics · Physics 2014-02-20 Anatoly K. Nekrasov

Magnetosphere at ion kinetic scales, or mini-magnetosphere, possesses unusual features as predicted by numerical simulations. However, there are practically no data on the subject from space observations and the data which are available are…

How the turbulent energy cascade develops below the magnetohydrodynamic scales in space and astrophysical plasmas is a major open question. Here, we measure the power spectrum of magnetic fluctuations in Parker Solar Probe's observations…

A magnetically dominated plasma driven by motions on boundaries at which magnetic field lines are anchored is forced to dissipate the work being done upon it, no matter how small the electrical resistivity. Numerical experiments have…

Astrophysics · Physics 2007-05-23 Aake Nordlund

We investigate the question of whether ambipolar diffusion (ion-neutral drift) determines the smallest length and mass scale on which structure forms in a turbulent molecular cloud. We simulate magnetized turbulence in a mostly neutral,…

Astrophysics · Physics 2009-11-13 Jeffrey S. Oishi , Mordecai-Mark Mac Low

The anisotropic nature of solar wind magnetic turbulence fluctuations is investigated scale-by-scale using high cadence in-situ magnetic field measurements from the Cluster and ACE spacecraft missions. The data span five decades in scales…

We study a model of weakly ionized, protostellar accretion discs that are threaded by a large-scale, ordered magnetic field and power a centrifugally driven wind. We consider the limiting case where the wind is the main repository of the…

Solar and Stellar Astrophysics · Physics 2015-05-14 A. Königl , R. Salmeron , M. Wardle