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Related papers: Simulations of waves in sunspots

200 papers

Sunspots are transient, magnetically intense features that host oscillations linked to magnetohydrodynamic (MHD) waves. These waves may contribute to plasma heating and drive mass flows in the solar wind. Beyond their energetic role, they…

Solar and Stellar Astrophysics · Physics 2026-05-20 Kartika Sangal , A. K. Srivastava , Libo Fu , Ding Yuan , Song Feng , Yuandeng Shen

Computational heliophysics has shed light on the fundamental physical processes inside the Sun, such as the differential rotation, meridional circulation, and dynamo-generation of magnetic fields. However, despite the substantial advances,…

Solar and Stellar Astrophysics · Physics 2023-01-25 A. G. Kosovichev , G. Guerrero , A. M. Stejko , V. V. Pipin , A. V. Getling

Investigation of propagation, conversion, and scattering of MHD waves in the Sun is very important for understanding the mechanisms of observed oscillations and waves in sunspots and active regions. We have developed 3D linear MHD numerical…

Astrophysics · Physics 2011-02-11 K. V. Parchevsky , A. G. Kosovichev

Recent progress in theoretical modeling of a sunspot is reviewed. The observed properties of umbral dots are well reproduced by realistic simulations of magnetoconvection in a vertical, monolithic magnetic field. To understand the penumbra,…

Solar and Stellar Astrophysics · Physics 2015-05-13 John H. Thomas

Sunspots are regions of decreased brightness on the visible surface of the Sun (photosphere) that are associated with strong magnetic fields. They have been found to be locations associated with solar flares, which occur when energy stored…

Solar and Stellar Astrophysics · Physics 2013-01-24 Sophie A. Murray

Global dynamo simulations solving the equations of magnetohydrodynamics (MHD) have been a tool of astrophysicists who try to understand the magnetism of the Sun for several decades now. During recent years many fundamental issues in dynamo…

Solar and Stellar Astrophysics · Physics 2011-07-08 P. J. Käpylä

Magnetohydrodynamic (MHD) wave activity is ubiquitous in the solar atmosphere. MHD seismology aims to determine difficult to measure physical parameters in solar atmospheric magnetic and plasma structures by a combination of observed and…

Solar and Stellar Astrophysics · Physics 2015-06-04 Inigo Arregui

The sunspot penumbra is a transition zone between the strong vertical magnetic field area (sunspot umbra) and the quiet Sun. The penumbra has a fine filamentary structure that is characterized by magnetic field lines inclined toward the…

Solar and Stellar Astrophysics · Physics 2010-12-02 I. N. Kitiashvili , A. G. Kosovichev , N. N. Mansour , A. A. Wray

Simulations show for the first time how the magnetic fields that produce solar flares can extend out of the Sun by acquiring a twist.

Solar and Stellar Astrophysics · Physics 2016-03-09 Axel Brandenburg

While sunspots are easily observed at the solar surface, determining their subsurface structure is not trivial. There are two main hypotheses for the subsurface structure of sunspots: the monolithic model and the cluster model. Local…

The magnetic and convective nature of the Sun's photosphere provides a unique platform from which generated waves can be modelled, observed, and interpreted across a wide breadth of spatial and temporal scales. As oscillations are generated…

Solar and Stellar Astrophysics · Physics 2020-12-01 David B. Jess , Peter H. Keys , Marco Stangalini , Shahin Jafarzadeh

This article provides a survey on some main results and recent developments in the mathematical theory of water waves. More precisely, we briefly discuss the mathematical modeling of water waves and then we give an overview of local and…

History and Overview · Mathematics 2018-05-17 Wolf-Patrick Düll

The goal of helioseismology is to provide accurate information about the Sun's interior from the observations of the wave field at its surface. In the last three decades, both global and local helioseismology studies have made significant…

It is now well established that the plasma in galaxy clusters is magnetized. In some cases, at least, the field is strong enough to be dynamically important. Perhaps this is the time to move past simple detection experiments, and to work…

Astrophysics · Physics 2007-05-23 J. A. Eilek

This chapter reviews the recent progress made mainly during the last two decades on wave turbulence in magnetized plasmas (MHD, Hall MHD and electron MHD) in the incompressible and compressible cases. The emphasis is made on homogeneous and…

Solar and Stellar Astrophysics · Physics 2015-03-19 Sebastien Galtier

Recent high-resolution observations of sunspot oscillations using simultaneously operated ground- and space-based telescopes reveal the intrinsic connection between different layers of the solar atmosphere. However, it is not clear whether…

Solar and Stellar Astrophysics · Physics 2015-10-13 S. Krishna Prasad , D. B. Jess , Elena Khomenko

Time-distance helioseismic measurements in surface- and deep-focus geometries for wave-paths that distinguish surface magnetic contributions from those due to deeper perturbations beneath a large sunspot are presented and analysed. Travel…

Astrophysics · Physics 2008-02-21 S. P. Rajaguru

We present results from numerical simulations of the interaction of internal gravity waves (IGW) with magnetic fields in the radiative interior of the Sun. In this second paper, the waves are forced self-consistently by an overlying…

Solar and Stellar Astrophysics · Physics 2015-05-20 T. M. Rogers , K. B. MacGregor

We applied the method of continuous wavelet-transform to high-quality time-frequency analysis to the sets of observations of relative sunspot numbers. Wavelet analysis of these data reveals the following pattern: at the same time there are…

Solar and Stellar Astrophysics · Physics 2015-12-15 A. A. Borisov , E. A. Bruevich , V. V. Bruevich , I. K. Rozgacheva , E. V. Shimanovskaya

We present results on modeling solar pores and sunspots using 2D axisymmetric magneto-hydrodynamic (MHD) simulations. These models are helpful for understanding the mechanisms of magnetic field concentration in sunspots, and the large-scale…

Solar and Stellar Astrophysics · Physics 2010-06-22 T. Hartlep , F. H. Busse , N. E. Hulburt , A. G. Kosovichev