English
Related papers

Related papers: Three-dimensional solar active region magnetohydro…

200 papers

We have used the AMR hydrodynamic code, MG, to perform idealised 3D MHD simulations of the formation of clumpy and filamentary structure in a thermally unstable medium without turbulence. A stationary thermally unstable spherical diffuse…

Astrophysics of Galaxies · Physics 2016-03-23 C. J. Wareing , J. M. Pittard , S. A. E. G. Falle , S. Van Loo

Plasma beta is an important and fundamental physical quantity in order to understand plasma dynamics, particularly in the context of magnetically active stars, because it tells about the domination of magnetic versus thermodynamic processes…

Solar and Stellar Astrophysics · Physics 2017-11-30 Philippe-A. Bourdin

With the development of new instrumentation providing measurements of solar photospheric vector magnetic fields, we need to develop our understanding of the effects of current density on coronal magnetic field configurations. The object is…

Astrophysics · Physics 2009-11-13 S. Regnier , E. R. Priest

Studying the hemispheric distribution of active regions (ARs) with different magnetic morphology may clarify the features of the dynamo process that is hidden under the photospheric level. The magnetic flux data for 3047 ARs from the CrAO…

Solar and Stellar Astrophysics · Physics 2024-07-10 A. Zhukova

The well-observed acoustic halo is an enhancement in time-averaged Doppler velocity and intensity power with respect to quiet-sun values which is prominent for weak and highly inclined field around the penumbra of sunspots and active…

Solar and Stellar Astrophysics · Physics 2016-01-27 Carlos Rijs , S. P. Rajaguru , Damien Przybylski , Hamed Moradi , Paul S. Cally , Sergiy Shelyag

The emergence of dipolar magnetic features on the solar surface is an idealization. Most of the magnetic flux emergence occurs in complex multipolar regions. Here, we show that the surface pattern of magnetic structures alone can reveal the…

Solar and Stellar Astrophysics · Physics 2018-12-11 Philippe-A. Bourdin , Axel Brandenburg

Data for 3046 solar active regions (ARs) observed since May 12, 1996 to December 27, 2021 were utilized to explore how the magnetic fluxes from ARs of different complexity follow the solar cycle. Magnetograms from the Michelson Doppler…

Solar and Stellar Astrophysics · Physics 2022-12-15 Valentina I. Abramenko , Regina A. Suleymanova , Anastasija V. Zhukova

In order to understand the conditions which lead a highly magnetized, relativistic plasma to become unstable, and in such cases how the plasma evolves, we study a prototypical class of magnetostatic equilibria where the magnetic field…

High Energy Astrophysical Phenomena · Physics 2015-08-31 William E. East , Jonathan Zrake , Yajie Yuan , Roger D. Blandford

The fully three dimensional governing equations in the electron magnetohydrodynamic (EMHD) regime for a plasma with inhomogeneous density is obtained. These equations in the two dimensional (2-D) limit can be cast in terms of the evolution…

Plasma Physics · Physics 2009-11-13 Sharad Kumar Yadav , Amita Das , Predhiman Kaw

In this review many of the well known tools for the analysis of Complex systems are used in order to study the global coupling of the turbulent convection zone with the solar atmosphere where the magnetic energy is dissipated explosively.…

Solar and Stellar Astrophysics · Physics 2016-11-03 Loukas Vlahos , Heinz Isliker

Global magnetohydrodynamic (MHD) instabilities are investigated in a computationally tractable two-dimensional model of the solar tachocline. The model's differential rotation yields stability in the absence of a magnetic field, but if a…

Plasma Physics · Physics 2019-02-19 Abigail Plummer , J. B. Marston , S. M. Tobias

High-resolution observations show the fine structure of the global equilibrium magnetic field configuration in solar atmosphere to be essentially different from that assumed in the traditional 'potential + force-free' field scenarios. The…

Solar and Stellar Astrophysics · Physics 2012-05-01 L. A. Pustil'nik , N. R. Ikhsanov , N. G. Beskrovnaya

The systematic variation of solar active region (AR) properties with their magnetic flux has been the subject of numerous studies but the proposed scaling laws still vary rather widely. A correct representation of these laws and the…

Solar and Stellar Astrophysics · Physics 2026-04-24 Guilherme A. L. Nogueira , Robertus Erdelyi , Ruihui Wang , Kristof Petrovay

An analytical representation of the interstellar magnetic field in the vicinity of the heliosphere is derived. The three-dimensional field structure close to the heliopause is calculated as a solution of the induction equation under the…

Solar and Stellar Astrophysics · Physics 2015-06-11 Christian Röken , Jens Kleimann , Horst Fichtner

We present results from global, three-dimensional magnetohydrodynamic (MHD) simulations of the solar wind/magnetosphere interaction. These MHD simulations are used to study ultra low frequency (ULF) pulsations in the Earth's magnetosphere…

Space Physics · Physics 2010-10-20 S. G. Claudepierre , S. R. Elkington , M. Wiltberger

The close connection of magnetic field structure on the one hand and observable features of complex ARs with high flare efficiency on the other one is investigated in frames of so-called dynamic classification of flaring magnetic…

Astrophysics · Physics 2007-05-23 R. N. Ikhsanov , Yu. V. Marushin

Strong solar flares and coronal mass ejections, here defined not only as the bursts of electromagnetic radiation but as the entire process in which magnetic energy is released through magnetic reconnection and plasma instability, emanate…

Solar and Stellar Astrophysics · Physics 2019-05-29 Shin Toriumi , Haimin Wang

We present the first demonstration of the negative effective magnetic pressure instability in direct numerical simulations of stably stratified, externally forced, isothermal hydromagnetic turbulence in the regime of large plasma beta. By…

Solar and Stellar Astrophysics · Physics 2011-10-05 Axel Brandenburg , Koen Kemel , Nathan Kleeorin , Dhrubaditya Mitra , Igor Rogachevskii

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

We present a novel magnetohydrostatic numerical model that solves directly for the force-balanced magnetic field in the solar corona. This model is constructed with Radial Basis Function Finite Differences (RBF-FD), specifically 3D…

Solar and Stellar Astrophysics · Physics 2022-05-11 Nathaniel H. Mathews , Natasha Flyer , Sarah E. Gibson
‹ Prev 1 4 5 6 7 8 10 Next ›