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Related papers: Coronal influence on dynamos

200 papers

We perform a numerical parameter study to determine what effect varying differential rotation and flux emergence has on a star's non-potential coronal magnetic field. In particular we consider the effects on the star's surface magnetic…

Solar and Stellar Astrophysics · Physics 2016-03-11 G. P. S. Gibb , D. H. Mackay , M. M. Jardine , A. R. Yeates

We present in this Letter the first global comparison between traditional line-tied steady state magnetohydrodynamic models and a new, fully time-dependent thermodynamic magnetohydrodynamic simulation of the global corona. The maps are…

Solar and Stellar Astrophysics · Physics 2023-06-22 Emily I. Mason , Roberto Lionello , Cooper Downs , Jon A. Linker , Ronald M. Caplan

Here, we present numerical simulations of magnetic flux buoyantly rising from a granular convection zone into the low corona. We study the complex interaction of the magnetic field with the turbulent plasma. The model includes the radiative…

Space Physics · Physics 2015-05-18 Fang Fang , Ward Manchester , William P. Abbett , Bart van der Holst

Spherical solar dynamo simulations are performed. Self-consistent, fully compressible magnetohydrodynamic system with a stably stratified layer below the convective envelope is numerically solved with a newly developed simulation code based…

Solar and Stellar Astrophysics · Physics 2015-06-15 Youhei Masada , Kohei Yamada , Akira Kageyama

Coronal jets are transient, collimated eruptions that occur in regions of predominantly open magnetic field in the solar corona. Our understanding of these events has greatly evolved in recent years but several open questions, such as the…

Solar and Stellar Astrophysics · Physics 2015-12-01 T. Torok , R. Lionello , V. S. Titov , J. E. Leake , Z. Mikic , J. A. Linker , M. G. Linton

We consider the effect of a subadiabatic layer at the base of the convection zone on convection itself and the associated large-scale dynamos in spherical wedge geometry. We use a heat conduction prescription based on the Kramers opacity…

Solar and Stellar Astrophysics · Physics 2019-12-16 Petri J. Käpylä , Mariangela Viviani , Maarit J. Käpylä , Axel Brandenburg , Federico Spada

Selected topics in solar dynamo theory are being highlighted. The possible relevance of the near-surface shear layer is discussed. The role of turbulent downward pumping is mentioned in connection with earlier concerns that a…

Solar and Stellar Astrophysics · Physics 2009-05-09 Axel Brandenburg

Plasma in the Sun's hot corona expands into the heliosphere as a supersonic and highly magnetized solar wind. This paper provides an overview of our current understanding of how the corona is heated and how the solar wind is accelerated.…

Solar and Stellar Astrophysics · Physics 2015-08-19 S. R. Cranmer , M. Asgari-Targhi , M. P. Miralles , J. C. Raymond , L. Strachan , H. Tian , L. N. Woolsey

Magnetic fields generated in the Sun's interior by the solar dynamo mechanism drive solar activity over a range of time-scales. While space-based observations of the Sun's corona exist only for few decades, direct sunspot observations exist…

Solar and Stellar Astrophysics · Physics 2023-07-03 Soumyaranjan Dash , Dibyendu Nandy , Ilya Usoskin

Understanding the evolution of the complex magnetic fields found in solar active regions is an active area of research. There are numerous models for such fields which range in their complexity due to the number of known physical effects…

Solar and Stellar Astrophysics · Physics 2025-02-26 Oliver Rice , Christopher Prior

Detailed hydrodynamic modeling explained several features of a fragment of the core of a Coronal Mass Ejection observed with SoHO/UVCS at 1.7 Ro on 12 December 1997, but some questions remained unsolved. We investigate the role of the…

Astrophysics · Physics 2007-05-23 P. Pagano , F. Reale , S. Orlando , G. Peres

We present simulations modeling closed regions of the solar corona threaded by a strong magnetic field where localized photospheric vortical motions twist the coronal field lines. The linear and nonlinear dynamics are investigated in the…

Solar and Stellar Astrophysics · Physics 2013-06-20 A. F. Rappazzo , M. Velli , G. Einaudi

The magnetic field in the Sun's corona stores energy that can be released to heat the coronal plasma and drive solar eruptions. Measurements of the global coronal magnetic field have been limited to a few snapshots. We present observations…

Solar and Stellar Astrophysics · Physics 2024-10-23 Zihao Yang , Hui Tian , Steven Tomczyk , Xianyu Liu , Sarah Gibson , Richard J. Morton , Cooper Downs

Many stars exhibit strong magnetic fields, some of which are thought to be of primordial origin and others a sign of magnetic dynamo processes. We briefly review the results of observational studies of solar-type stars seeking to evaluate…

Astrophysics · Physics 2007-05-23 Allan Sacha Brun

Arguments are presented in favor of the idea that the solar dynamo may operate not just at the bottom of the convection zone, i.e. in the tachocline, but it may operate in a more distributed fashion in the entire convection zone. The…

Astrophysics · Physics 2007-05-23 Axel Brandenburg

We investigate the effect of coronal temperature on the formation process of solar chromospheric jets using two-dimensional magnetohydrodynamic simulations of the region from the upper convection zone to the lower corona. We develop a new…

Solar and Stellar Astrophysics · Physics 2015-10-28 H. Iijima , T. Yokoyama

Solar corona is much hotter than lower layers of the solar atmosphere-photosphere and chromosphere. The coronal temperature is up to 1MK in quiet sun areas, while up to several MK in active regions, which implies a key role of magnetic…

Solar and Stellar Astrophysics · Physics 2025-06-24 Gregory D. Fleishman , Alexey A. Kuznetsov , Gelu M. Nita

Vortex flows have been found in the photosphere, chromosphere and low corona in observations and simulations. It has been suggested that vortices play an important role for channeling energy and plasma into the corona, but the impact of…

Solar and Stellar Astrophysics · Physics 2023-07-05 C. Breu , H. Peter , R. Cameron , S. K. Solanki

The atmosphere of the Sun is highly structured and dynamic in nature. From the photosphere and chromosphere into the transition region and the corona plasma-$\beta$ changes from above to below one, i.e. while in the lower atmosphere the…

Astrophysics · Physics 2008-11-26 H. Peter

Several solar-like stars exhibit cyclic magnetic activity similar to the Sun as found in photospheric and chromospheric emission. We want to understand the physical mechanism involved in rotational dependence of these activity cycle…

Solar and Stellar Astrophysics · Physics 2018-08-22 Jörn Warnecke