English
Related papers

Related papers: Flux emergence in a magnetized convection zone

200 papers

Context: The expansion of network magnetic fields with height is a fundamental property of flux tube models. A rapid expansion is required to form a magnetic canopy. Aims: We characterize the observed expansion properties of magnetic…

Solar and Stellar Astrophysics · Physics 2015-05-19 A. Pietarila , R. Cameron , S. K. Solanki

The role of turbulence in current generation and self-excitation of magnetic fields has been studied in the geometry of a mechanically driven, spherical dynamo experiment, using a three dimensional numerical computation. A simple impeller…

Plasma Physics · Physics 2009-11-11 R. A. Bayliss , C. B. Forest , M. D. Nornberg , E. J. Spence , P. W. Terry

A plethora of solar dynamic events, such as the formation of active regions, the emission of jets and the occurrence of eruptions is often associated to the emergence of magnetic flux from the interior of the Sun to the surface and above.…

Solar and Stellar Astrophysics · Physics 2019-06-12 V. Archontis , P. Syntelis

We investigate the rising flux tube and the formation of sunspots in an unprecedentedly deep computational domain that covers the whole convection zone with a radiative magnetohydrodynamics simulation. Previous calculations had shallow…

Solar and Stellar Astrophysics · Physics 2020-04-08 H. Hotta , H. Iijima

We present a series of numerical sunspot models addressing the subsurface field and flow structure in up to 16 Mm deep domains covering up to 2 days of temporal evolution. Changes in the photospheric appearance of the sunspots are driven by…

Solar and Stellar Astrophysics · Physics 2015-05-28 Matthias Rempel

This paper considers a possibility of magnetic-field generation by local turbulent flows at the bottom of convective zone. The cycle of magnetic-field generation in this model can be represented in the form of sequency of processes. There…

Solar and Stellar Astrophysics · Physics 2013-10-18 Andrey G. Tlatov

Observations of magnetic clouds, within interplanetary coronal mass ejections (ICMEs), are often well described by flux rope models. Most of these assume either a cylindrical or toroidal geometry. In some cases, these models are also…

Solar and Stellar Astrophysics · Physics 2022-12-07 Andreas J. Weiss , Teresa Nieves-Chinchilla , Christian Möstl , Martin A. Reiss , Tanja Amerstorfer , Rachel L. Bailey

Magnetic flux ropes (MFRs) are one kind of fundamental structures in the solar physics, and involved in various eruption phenomena. Twist, characterizing how the magnetic field lines wind around a main axis, is an intrinsic property of…

Solar and Stellar Astrophysics · Physics 2017-02-01 Yuming Wang , Bin Zhuang , Qiang Hu , Rui Liu , Chenglong Shen , Yutian Chi

Over the last few years, numerical models of the behavior of solar magnetic flux tubes have gone from using methods that were essentially one-dimensional (i.e. the thin flux tube approximation), over more or less idealized two-dimensional…

Astrophysics · Physics 2007-05-23 Bertil Dorch

3D simulations of magnetic flux emergence are carried out in a computational domain spanning the upper layers of the convection zone to the lower corona. We use the Oslo Staggered Code to solve the full MHD equations with non-grey and NLTE…

Solar and Stellar Astrophysics · Physics 2009-08-11 J. Martinez-Sykora , V. Hansteen , M. Carlsson

We perform 3D radiation-magnetohydrodynamic simulations of the evolution of the fallback debris after a tidal disruption event. We focus on studying the effects of magnetic fields on the formation and early evolution of the accretion flow.…

High Energy Astrophysical Phenomena · Physics 2025-10-28 Maria Renee Meza , Xiaoshan Huang , Shane W. Davis , Yan-Fei Jiang

We study an evolving bipolar active region that exhibits flux cancellation at the internal polarity inversion line, the formation of a soft X-ray sigmoid along the inversion line and a coronal mass ejection. The evolution of the…

Solar and Stellar Astrophysics · Physics 2010-11-05 L. M. Green , B. Kliem , A. J. Wallace

In this article, the physical processes occurring in the convective layer and the photosphere of the Sun and their connection to the formation of active regions (ARs) and the development of the corresponding magnetic field are explored.…

Solar and Stellar Astrophysics · Physics 2024-02-22 Aidar M. Sadykov , Sergey A. Krasotkin

Solar filaments often exhibit rotation and deflection during eruptions, which would significantly affect the geoeffectiveness of the corresponding coronal mass ejections (CMEs). Therefore, understanding the mechanisms that lead to such…

Solar and Stellar Astrophysics · Physics 2023-08-21 Jinhan Guo , Ye Qiu , Yiwei Ni , Yang Guo , Chuan Li , Yuhang Gao , Brigitte Schmieder , Stefaan Poedts , Pengfei Chen

We study the influence of fringing magnetic fields on turbulent thermal convection in a horizontally extended rectangular domain. The magnetic field is created in the gap between two semi-infinite planar magnetic poles, with the convection…

Fluid Dynamics · Physics 2023-05-04 Shashwat Bhattacharya , Thomas Boeck , Dmitry Krasnov , Jörg Schumacher

Observations of rapidly rotating solar-like stars show a significant mixture of opposite-polarity magnetic fields within their polar regions. To explain these observations, models describing the surface transport of magnetic flux demand the…

Astrophysics · Physics 2009-11-11 V. Holzwarth , D. H. Mackay , M. Jardine

It has been observationally well established that the magnetic configurations most favorable for producing energetic flaring events reside in delta-spots, a class of sunspots defined as having opposite polarity umbrae sharing a common…

Solar and Stellar Astrophysics · Physics 2018-09-19 Kalman J. Knizhnik , Mark G. Linton , C. Richard DeVore

The operation of the solar global dynamo appears to involve many dynamical elements. Self-consistent MHD simulations which realistically incorporate all of these processes are not yet computationally feasible, though some elements can now…

Astrophysics · Physics 2008-11-26 Allan Sacha Brun , Mark S. Miesch , Juri Toomre

Context. Active regions (ARs) appear in the solar atmosphere as a consequence of the emergence of magnetic flux tubes. The presence of elongated magnetic polarities in line-of-sight (LOS) magnetograms indicates the existence of twist in the…

Solar and Stellar Astrophysics · Physics 2022-09-14 M. Poisson , F. Grings , C. H. Mandrini , M. López-Fuentes , P. Démoulin

We study the pumping of magnetic flux in three-dimensional compressible magnetoconvection in the context of stellar dynamos. The simulation domain represents a rectangular section from the lower part of a stellar convection zone plus the…

Astrophysics · Physics 2009-11-07 M. Ossendrijver , M. Stix , A. Brandenburg , G. Ruediger