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Related papers: Models and Observations of Sunspot Penumbrae

200 papers

In recent years solar oscillations have been studied in great detail, both observationally and theoretically; so, perhaps, the Sun currently is the best understood pulsating star. The observational studies include long, almost uninterrupted…

Solar and Stellar Astrophysics · Physics 2010-02-01 A. G. Kosovichev

The evolution of small magnetic features in quiet regions of the Sun provides a unique window to probing solar magneto-convection. Here we analyze small scale magnetic features in the quiet Sun, using the high resolution, seeing-free…

Solar and Stellar Astrophysics · Physics 2017-02-01 L. S. Anusha , Sami K. Solanki , Johann Hirzberger , Alex Feller

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

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

Using a reconstruction of sunspot numbers stretching over multiple millennia, we analyze the statistics of the occurrence of grand minima and maxima and set new observational constraints on long-term solar and stellar dynamo models. We…

Astrophysics · Physics 2014-11-18 I. G. Usoskin , S. K. Solanki , G. A. Kovaltsov

I describe the current status of the solar neutrino problem, summarizing the arguments that its resolution will require new particle physics. The phenomenon of matter-enhanced neutrino oscillations is reviewed. I consider the implications…

Nuclear Theory · Physics 2007-05-23 W. C. Haxton

One-dimensional stellar evolution models have been successful at representing the structure and evolution of stars in diverse astrophysical contexts, but complications have been noted in the context of young, magnetically active stars, as…

Solar and Stellar Astrophysics · Physics 2020-03-11 Garrett Somers , Lyra Cao , Marc H. Pinsonneault

The main aim of this paper is to introduce the most important observables that help us to investigate stellar dynamos and compare those to the modeling results. We give an overview of the available observational methods and data processing…

Solar and Stellar Astrophysics · Physics 2014-08-27 Zsolt Kovari , Katalin Olah

(adapted)Considering recent observations challenging the traditional magnetar model, we explore the wind braking of magnetars. There is evidence for strong multipole magnetic fields in active magnetars, but the dipole field inferred from…

High Energy Astrophysical Phenomena · Physics 2015-06-05 H. Tong , R. X. Xu , L. M. Song , G. J. Qiao

The development of observational techniques has inriched our knowledge of supernova remnants. In this paper, we review the main progresses in the last decade, including new discoveries of supernova remnants and the associated (rare type of)…

Astrophysics · Physics 2008-10-23 Xuejuan Yang , Fangjun Lu , Wenwu Tian

The flows in and around sunspots are rich in detail. Starting with the Evershed flow along low-lying flow channels, which are cospatial with the horizontal penumbral magnetic fields, Evershed clouds may continue this motion at the periphery…

Solar and Stellar Astrophysics · Physics 2015-05-19 Carsten Denker , Meetu Verma

Observations of the Sun and solar-type stars continue to reveal phenomena whose understanding is very likely to require a nonlinear framework. Here we shall concentrate on two such phenomena, namely the grand minima type behaviour observed…

Astrophysics · Physics 2007-05-23 Reza Tavakol , Eurico Covas

We demonstrate that the solar and atmospheric neutrino data as well as the recent result of the LSND experiment cannot be satisfied simultaneously with three light neutrinos if we consider the mass degeneracy for two neutrinos in the…

High Energy Physics - Phenomenology · Physics 2007-05-23 Ambar Ghosal , Asim K. Ray

Continuous observations of sunspot penumbrae with the Solar Optical Telescope aboard \textit{Hinode} clearly show that the outer boundary of the penumbra fluctuates around its averaged position. The penumbral outer boundary moves inward…

Two-dimensional hydrodynamical simulations are presented from the formation up to the late evolution of planetary nebula, for 6 different stellar models from 1 to 5 Mo. The hydrodynamical models use stellar evolution calculations as inner…

Solar and Stellar Astrophysics · Physics 2025-10-13 Guillermo Garcia-Segura , Arturo Manchado , Jesus A. Toala , Martin A. Guerrero , Alberto J. Castro-Tirado

A sunspot penumbra is observationally examined to reveal properties of small-scale flow structures and how they are related to the filamentary magnetic structures and the Evershed flow. We also study how the photospheric dynamics is related…

Solar and Stellar Astrophysics · Physics 2015-05-19 Y. Katsukawa , J. Jurcak

Pulsar Wind Nebulae (PWNe) are bubbles or relativistic plasma that form when the pulsar wind is confined by the SNR or the ISM. Recent observations have shown a richness of emission features that has driven a renewed interest in the…

High Energy Astrophysical Phenomena · Physics 2015-05-19 N. Bucciantini

Context. Solar eruptions and high flare activity often accompany the rapid rotation of sunspots. The study of sunspot rotation and the mechanisms driving this motion are therefore key to our understanding of how the solar atmosphere attains…

Solar and Stellar Astrophysics · Physics 2015-10-14 Z. Sturrock , A. W. Hood , V. Archontis , C. M. McNeill

Diverse experimental constraints now motivate models of supersymmetry breaking in which some superpartners have masses well above the weak scale. Three alternatives are focus point supersymmetry and inverted hierarchy models, which embody a…

High Energy Physics - Phenomenology · Physics 2010-04-05 Jonathan L. Feng , Frank Wilczek

Observations of a large solar flare of December 13, 2006, using Solar Optical Telescope (SOT) on Hinode spacecraft revealed high-frequency oscillations excited by the flare in the sunspot chromosphere. These oscillations are observed in the…

Astrophysics · Physics 2009-11-13 A. G. Kosovichev , T. Sekii