English
Related papers

Related papers: Hydraulic effects in a radiative atmosphere with i…

200 papers

Solar wind is probably the best laboratory to study turbulence in astrophysical plasmas. In addition to the presence of magnetic field, the differences with neutral fluid isotropic turbulence are: weakness of collisional dissipation and…

Solar and Stellar Astrophysics · Physics 2015-06-16 Olga Alexandrova , Christopher H. K. Chen , Luca Sorriso-Valvo , Timothy S. Horbury , Stuart D. Bale

The formation of shocks within the solar atmosphere remains one of the few observable signatures of energy dissipation arising from the plethora of magnetohydrodynamic waves generated close to the solar surface. Active region observations…

Context. Recent observations of solar prominences show the presence of turbulent flows that may be caused by Kelvin-Helmholtz instabilites (KHI). However, the observed flow velocities are below the classical threshold for the onset of KHI…

Solar and Stellar Astrophysics · Physics 2016-09-21 David Martínez-Gómez , Roberto Soler , Jaume Terradas

Radiation pressure can be dynamically important in star-forming environments such as ultra-luminous infrared and submillimeter galaxies. Whether and how radiation drives turbulence and bulk outflows in star formation sites is still unclear.…

Astrophysics of Galaxies · Physics 2015-10-15 Benny Tsz-Ho Tsang , Milos Milosavljevic

Turbulence is often invoked to explain the origin of nonthermal particles in space and astrophysical plasmas. By means of 3D fully kinetic particle-in-cell simulations, we demonstrate that turbulence in low-$\beta$ plasmas ($\beta$ is the…

High Energy Astrophysical Phenomena · Physics 2022-09-16 Luca Comisso , Lorenzo Sironi

The author presents a model for variability of the flux and polarization of blazars in which turbulent plasma flowing at a relativistic speed down a jet crosses a standing conical shock. The shock compresses the plasma and accelerates…

High Energy Astrophysical Phenomena · Physics 2015-06-18 Alan P. Marscher

Kinetic effects in plasma flow due to a finite ion temperature and ion reflections in a converging-diverging magnetic nozzle are investigated with collisionless quasineutral hybrid simulations with kinetic ions and isothermal Boltzmann…

Plasma Physics · Physics 2022-10-25 Marilyn Jimenez , Andrei Smolyakov , Oleksandr Chapurin , Peter Yushmanov

Theoretical and observational studies on the turbulence of the interstellar medium developed fast in the past decades. The theory of supersonic magnetized turbulence, as well as the understanding of projection effects of observed…

Astrophysics of Galaxies · Physics 2015-05-18 D. Falceta-Goncalves , A. Lazarian , M. Houde

We present the results of a 2-D, two fluid (ions and neutrals) simulation of the ambipolar filamentation process, in which a magnetized, weakly ionized plasma is stirred by turbulence in the ambipolar frequency range. The higher turbulent…

Astrophysics · Physics 2007-05-23 M. Franqueira , M. Tagger , A. I. Gomez de Castro

Context. Solar eruptions and high flare activity often accompany the rapid rotation of sunspots. The study of sunspot rotation and the mechanisms driving this motion are therefore key to our understanding of how the solar atmosphere attains…

Solar and Stellar Astrophysics · Physics 2015-10-14 Z. Sturrock , A. W. Hood , V. Archontis , C. M. McNeill

We show that the atmospheric and magnetic height variations are coupled in general MHS equilibria with gravity when isolated thin non-force-free flux tubes are present. In gas-dominated environments, as in stellar photospheres, flux tubes…

Astrophysics · Physics 2009-11-07 Laurence J. November

The processes occurring in the solar atmosphere are diverse and depend on many important factors. For example, from magnetic fields, their sudden changes, from emissions of substance from the depths of the Sun, distribution of shock waves…

Solar and Stellar Astrophysics · Physics 2012-12-11 A. T. Sarsembaeva , N. Zh. Takibayev , K. Kato

Sunspots and active regions observed on the solar surface are widely believed to be manifestations of compact predominantly-toroidal magnetic field structures (``flux tubes") that emerge by magnetic buoyancy from the deeper interior of the…

Solar and Stellar Astrophysics · Physics 2024-06-21 Bhishek Manek , Nicholas Brummell

Parker instability arises from the presence of magnetic fields in a plasma in a gravitational field such as the interstellar medium (ISM), wherein the magnetic buoyant pressure expels the gas and causes the gas to move along the field…

High Energy Astrophysical Phenomena · Physics 2011-09-07 Chih-Yueh Wang , Ying-Yi Lo , Chung-Ming Ko

The negative effective magnetic pressure instability operates on scales encompassing many turbulent eddies and is here discussed in connection with the formation of active regions near the surface layers of the Sun. This instability is…

Solar and Stellar Astrophysics · Physics 2013-09-10 Koen Kemel , Axel Brandenburg , Nathan Kleeorin , Dhrubaditya Mitra , Igor Rogachevskii

Magnetic fields emerging from the Sun's interior carry information about physical processes of magnetic field generation and transport in the convection zone. Soon after appearance on the solar surface the magnetic flux gets concentrated in…

Solar and Stellar Astrophysics · Physics 2009-11-13 A. G. Kosovichev

The ponderomotive force is suggested to be the main mechanism to produce the so-called first ionization potential (FIP) effect - the enrichment of low FIP elements observed in the outer solar atmosphere. It is well known that the ionization…

Solar and Stellar Astrophysics · Physics 2023-06-14 Juan Martínez-Sykora , Bart De Pontieu , Viggo H. Hansteen , Paola Testa , Q. M. Wargnier , Mikolaj Szydlarski

Alfv\'en waves are a particular class of magnetohydrodynamic waves relevant in many astrophysical and laboratory plasmas. In partially ionized plasmas the dynamics of Alfv\'en waves is affected by the interaction between ionized and neutral…

Solar and Stellar Astrophysics · Physics 2015-06-15 R. Soler , M. Carbonell , J. L. Ballester , J. Terradas

Context: The paradigm of convection in solar-like stars is questioned based on recent solar observations. Aims: The primary aim is to study the effects of surface-driven entropy rain on convection zone structure and flows. Methods:…

Solar and Stellar Astrophysics · Physics 2025-06-11 P. J. Käpylä

Context. Magnetohydrodynamic (MHD) waves are ubiquitous in the solar atmosphere. In magnetic waveguides resonant absorption due to plasma inhomogeneity naturally transfers wave energy from large-scale motions to small-scale motions. In the…

Solar and Stellar Astrophysics · Physics 2015-06-03 R. Soler , J. Andries , M. Goossens