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Related papers: Small-scale dynamos: From idealized models to sola…

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The magnetic activity of the Sun, as manifested in the sunspot cycle, originates deep within its convection zone through a dynamo mechanism which involves non-trivial interactions between the plasma and magnetic field in the solar interior.…

Solar and Stellar Astrophysics · Physics 2015-05-13 Dibyendu Nandy

In the quiet Sun, magnetic fields are usually observed as small-scale magnetic elements, `salt and pepper', covering the entire solar surface. By using 3D radiative MHD numerical simulations we demonstrate that these fields are a result of…

Solar and Stellar Astrophysics · Physics 2013-12-05 I. N. Kitiashvili , A. G. Kosovichev , N. N. Mansour , A. A. Wray

To understand solar and stellar dynamos combining local and global numerical modelling with long-term observations is a challenging task: even with state of the art computational methods and resources, the stellar parameter regime remains…

Solar and Stellar Astrophysics · Physics 2021-02-08 M. Viviani , A. Prabhu , J. Warnecke , L. Duarte , J. Pekkilä , M. Rheinhardt , M. J. Käpylä

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

Stellar dynamos are driven by complex couplings between rotation and turbulent convection, which drive global-scale flows and build and rebuild stellar magnetic fields. When stars like our sun are young, they rotate much more rapidly than…

We investigate small-scale dynamo action in the solar convection zone through a series of high resolution MHD simulations in a local Cartesian domain with 1$R_\odot$ (solar radius) of horizontal extent and a radial extent from 0.715 to…

Solar and Stellar Astrophysics · Physics 2015-06-23 H. Hotta , M. Rempel , T. Yokoyama

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

In order to clarify a possible role of small-scale dynamo in formation of solar magnetic field, we suggest an observational test for small-scale dynamo action based on statistics of anti-Hale sunspot groups. As we have shown, according to…

Solar and Stellar Astrophysics · Physics 2017-05-01 D. Sokoloff , A. Khlystova , V. Abramenko

Our understanding of stellar dynamos has largely been driven by the phenomena we have observed of our own Sun. Yet, as we amass longer-term datasets for an increasing number of stars, it is clear that there is a wide variety of stellar…

Solar and Stellar Astrophysics · Physics 2019-01-30 Maria A. Weber

The recent observational, theoretical, and numerical progress made in understanding stellar magnetism is discussed. Particularly, this review will cover the physical processes thought to be at the origin of these magnetic fields and their…

Solar and Stellar Astrophysics · Physics 2017-11-08 Kyle Augustson

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

Some of the small-scale solar magnetic flux can be attributed to a small-scale dynamo (SSD) operating in the near-surface convection. The SSD fields have consequences for solar granular convection, basal flux, as well as chromospheric…

It has been recently shown numerically that a small-scale dynamo (SSD) instability could be possible in solar-like low magnetic Prandtl number plasmas. It has been proposed that the presence of SSD can potentially have a significant impact…

Solar and Stellar Astrophysics · Physics 2025-04-09 Jörn Warnecke , Maarit J. Korpi-Lagg , Matthias Rheinhard , Mariangela Viviani , Ameya Prabhu

An overview is given about recent developments and results of comprehensive simulations of magneto-convective processes in the near-surface layers and photosphere of the Sun. Simulations now cover a wide range of phenomena, from whole…

Solar and Stellar Astrophysics · Physics 2015-06-12 Manfred Schüssler

Spectropolarimetric observations show that many low-mass stars possess large-scale poloidal magnetic fields with considerable dipole component, which in some cases exhibit temporal dynamics - cycles or reversals. Although it is widely…

Solar and Stellar Astrophysics · Physics 2025-07-02 Anna Guseva , Ludovic Petitdemange , Charly Pinçon

This paper provides a brief overview of dynamo scaling relationships for the degree of equipartition between magnetic and kinetic energies. Three basic approaches are adopted to explore these scaling relationships, with a first look at two…

Solar and Stellar Astrophysics · Physics 2017-01-11 Kyle Augustson , Stéphane Mathis , Allan Sacha Brun

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

In this work, we have studied the variability and frequency of occurrence of the grand minima using kinematic dynamo models of one solar mass star with different rotation rates and depths of convection zones. We specify the large-scale…

Solar and Stellar Astrophysics · Physics 2022-12-06 Vindya Vashishth

Advances in solar instrumentation have led to a widespread usage of time series to study the dynamics of solar features, specially at small spatial scales and at very fast cadences. Physical processes at such scales are determinant as…

Solar and Stellar Astrophysics · Physics 2015-06-19 S. Vargas Dominguez , J. Palacios , L. Balmaceda , I. Cabello , V. Domingo

While the presence of magnetic fields on low-mass stars is attributed to a dynamo process essentially driven by convective motions, the existence of magnetic fields on intermediate-mass stars has very likely other reasons. Presuming that…

Solar and Stellar Astrophysics · Physics 2013-09-30 Rainer Arlt