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Related papers: Simulations of waves in sunspots

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Motivated by the problem of local solar subsurface magnetic structure, we have used numerical simulation to investigate the propagation of waves through monolithic magnetic flux tubes of different size. A cluster model can be a good…

Solar and Stellar Astrophysics · Physics 2015-06-17 Khalil Daiffallah

The physics of Sunspots is a fascinating and demanding field of research in solar astronomy. Interaction of magnetic fields and plasma flows takes place in a tangled magnetic geometry and occurs on spatial scales that pose a continuous…

Solar and Stellar Astrophysics · Physics 2009-03-10 Alexandra Tritschler

The mysteries of sunspot penumbrae have been under an intense scrutiny for the past 10 years. During this time, some models have been proposed and refuted, while the surviving ones had to be modified, adapted and evolved to explain the…

Astrophysics · Physics 2009-11-05 J. M. Borrero

The magnetic cycle of the Sun, as manifested in the cyclic appearance of sunspots, significantly influences our space environment and space-based technologies by generating what is now termed as space weather. Long-term variation in the…

Solar and Stellar Astrophysics · Physics 2011-10-27 Dibyendu Nandy

Hydrodynamical simulations played an important role in understanding the dynamics and shaping of planetary nebulae in the past century. However, hydrodynamical simulations were just a first order approach. The new millennium arrived with…

Astrophysics · Physics 2015-06-24 Garcia-Segura

The structure of the surface layers of the Sun is changed by magnetic activity which, in turn, changes the eigenfrequencies of the acoustic modes. These frequency shifts have been observed both in low- and high-degree data, and are found to…

Astrophysics · Physics 2007-05-23 M. Cunha , M. Bruggen , D. O. Gough

We report 2D time-dependent non-linear magneto-hydrodynamical simulations of waves in the atmospheres of roAp stars. We explore a grid of simulations in a wide parameter space. The aim of our study is to understand the influence of the…

Solar and Stellar Astrophysics · Physics 2009-11-13 E. Khomenko , O. Kochukhov

The paper deals with electromagnetic effects associated with a radially symmetric system of progressive surface waves in the deep sea, induced by underwater oscillating sources or by dispersive decay of the initial localized perturbations…

Atmospheric and Oceanic Physics · Physics 2014-07-15 S. B. Kozitskiy

We present observational evidence for the presence of MHD waves in the solar photosphere deduced from SOHO/MDI Dopplergram velocity observations. The magneto-acoustic perturbations are observed as acoustic power enhancement in the sunspot…

Solar and Stellar Astrophysics · Physics 2013-07-10 S. Zharkov , S. Shelyag , V. Fedun , R. Erdélyi , M. J. Thompson

We describe the presence of wavefront dislocations in magnetohydrodynamic waves in stratified stellar atmospheres. Scalar dislocations such as edges and vortices can appear in Alfv\'en waves, as well as in general magneto-acoustic waves. We…

Solar and Stellar Astrophysics · Physics 2015-06-16 A. López Ariste , M. Collados , E. Khomenko

The goal of local helioseismology is to elicit three-dimensional information about the sub-surface (or far-side) structure and dynamics of the Sun from observations of the helioseismic wave field at the surface. The physical quantities of…

Solar and Stellar Astrophysics · Physics 2015-05-19 Hannah Schunker

Solar activity is controlled by the magnetic field, which also causes the variability of the solar irradiance that in turn is thought to influence the climate on Earth. The magnetic field manifests itself in the form of structures of…

Solar and Stellar Astrophysics · Physics 2013-07-10 T. L. Riethmüller

Within the last decade, due to significant improvements in the spatial and temporal resolution of chromospheric data, magnetohydrodynamic (MHD) wave studies in this fascinating region of the Sun's atmosphere have risen to the forefront of…

Solar and Stellar Astrophysics · Physics 2016-03-09 G. Verth , D. B. Jess

We present the results of numerical simulations of shock wave-driven jets in the solar atmosphere. The dependence of observable quantities like maximum velocity and deceleration on parameters such as the period and amplitude of initial…

Astrophysics · Physics 2011-02-11 L. Heggland , B. De Pontieu , V. H. Hansteen

In this review, our present day understanding of the Sun's global photospheric and coronal magnetic fields is discussed from both observational and theoretical viewpoints. Firstly, the large-scale properties of photospheric magnetic fields…

Solar and Stellar Astrophysics · Physics 2015-06-12 D. H. Mackay , A. R. Yeates

System-scale magnetohydrodynamic (MHD) waves within Earth's magnetosphere are often understood theoretically using box models. While these have been highly instructive in understanding many fundamental features of the various wave modes…

Space Physics · Physics 2022-02-01 M. O. Archer , D. J. Southwood , M. D. Hartinger , L. Rastaetter , A. N. Wright

The torsional oscillation is a well established observational fact and there are theoretical attempts for its description but no final solution has yet been accepted. One of the possible candidates for its cause is the presence of sunspots…

Solar and Stellar Astrophysics · Physics 2014-01-13 J. Muraközy , A. Ludmány

This work reviews our understanding of the magnetic fields observed in the quiet Sun. The subject has undergone a major change during the last decade (quiet revolution), and it will remain changing since the techniques of diagnostic…

Solar and Stellar Astrophysics · Physics 2011-05-03 J. Sanchez Almeida , M. Martinez Gonzalez

Magnetohydrodynamic simulations of core-collapse supernovae have become increasingly mature and important in recent years. Magnetic fields take center stage in scenarios for explaining hypernova explosions, but are now also considered in…

High Energy Astrophysical Phenomena · Physics 2024-03-29 Bernhard Müller

Three-dimensional magnetohydrodynamic simulations of the surface layers of the Sun intrinsically produce a predominantly horizontal magnetic field in the photosphere. This is a robust result in the sense that it arises from simulations with…

Solar and Stellar Astrophysics · Physics 2009-04-15 O. Steiner , R. Rezaei , R. Schlichenmaier , W. Schaffenberger , S. Wedemeyer-Böhm