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Related papers: Sunspot Structure

200 papers

Using SDO/HMI and SDO/AIA data for sunspot groups of the 24th solar cycle, we analyzed magnetic properties and He II 304 emission in leading and following sunspots separately. Simultaneous examination of umbral magnetic properties and…

Solar and Stellar Astrophysics · Physics 2015-11-24 Iu. S. Zagainova , V. G. Fainshtein , V. N. Obridko

Solar prominences and filaments (prominences projected against the solar disk) exhibit a large variety of fine structures which are well observed down to the resolution limit of ground-based telescopes. We describe the morphological aspects…

Astrophysics · Physics 2007-05-23 P. Heinzel

We present a catalog that we named MODEST containing depth-dependent information on the atmospheric conditions inside sunspot groups of all types. The catalog is currently composed of 942 observations of 117 individual active regions with…

Solar and Stellar Astrophysics · Physics 2024-07-17 J. S. Castellanos Durán , N. Milanovic , A. Korpi-Lagg , B. Löptien , M. van Noort , S. K. Solanki

Light bridge (LB) is bright structure crossing the umbra of sunspots and associated to the breakup or assembly of sunspots. In this paper, a LB is presented and studied using the observatory data obtained by {\it Hinode} satellites.…

Solar and Stellar Astrophysics · Physics 2019-05-07 S. Liu , D. Liu

This review provides an introduction to the generation and evolution of the Sun's magnetic field, summarising both observational evidence and theoretical models. The eleven year solar cycle, which is well known from a variety of observed…

Solar and Stellar Astrophysics · Physics 2011-10-17 Alan W. Hood , David W. Hughes

An analysis of the photometric growth and decay rates of sunspots and pores was carried out. According to the \textit{Solar Dynamics Observatory/Helioseismic and Magnetic Imager} (SDO/HMI) data for the period 05.2010-03-2025, $\approx…

Solar and Stellar Astrophysics · Physics 2025-06-30 Andrey Tlatov

The generation of magnetic flux in the solar interior and its transport from the convection zone into the photosphere, the chromosphere, and the corona will be in the focus of solar physics research for the next decades. With 4m class…

Solar and Stellar Astrophysics · Physics 2015-05-18 R. Schlichenmaier , N. Bello Gonzalez , R. Rezaei , T. A. Waldmann

In this work we selected one particular fibril from a high resolution solar chromosphere observation from the Dutch Open Telescope, and tried to obtain a broad picture of the intricate mechanism that might be incorporated in the multiple…

Solar and Stellar Astrophysics · Physics 2015-11-11 Emanuel Sungging Mumpuni , Dhani Herdiwijaya , Mitra Djamal , Thomas Djamaluddin

We observed an elongated filamentary bright structure inside the umbra of the big sunspot in active region NOAA 12529, which differs from the light bridges usually observed in sunspots for its morphology, magnetic configuration, and…

Solar and Stellar Astrophysics · Physics 2017-09-13 Salvo L. Guglielmino , Paolo Romano , Francesca Zuccarello

The number of spots on the surface of the Sun is one of the best tracers of solar variability we have. The sunspot number is not only known to change in phase with the 11-year solar cycles, but also to show variability on longer time…

Solar and Stellar Astrophysics · Physics 2019-06-27 Christoffer Karoff , Carsten Sønderskov Jørgensen , V. Senthamizh Pavai , Rainer Arlt

Many sunspots are surrounded by a radial outflow called the moat flow. We investigate the moat flow at two different heights of the solar atmosphere for a sunspot whose magnetic properties were reported in the first paper of this series. We…

Solar and Stellar Astrophysics · Physics 2014-11-20 H. Balthasar , K. Muglach

Inversions of spectropolarimetric observations of penumbral filaments deliver the stratification of different physical quantities in an optical depth scale. However, without establishing a geometrical height scale their three-dimensional…

Solar and Stellar Astrophysics · Physics 2013-03-14 K. G. Puschmann , B. Ruiz Cobo , V. Martínez Pillet

Previous helioseismology of sunspots has been sensitive to both the structural and magnetic aspects of sunspot structure. We aim to develop a technique that is insensitive to the magnetic component so the two aspects can be more readily…

Solar and Stellar Astrophysics · Physics 2018-06-07 T. L. Duvall , P. S. Cally , D. Przybylski , K. Nagashima , L. Gizon

Context: Solar pores are small sunspots lacking a penumbra that have a prevailing vertical magnetic field component. They can include light bridges at places with locally reduced magnetic field. Like sunspots, they exhibit a wide range of…

Solar and Stellar Astrophysics · Physics 2015-06-17 M. Sobotka , M. Švanda , J. Jurčák , P. Heinzel , D. Del Moro , F. Berrilli

We compute realistic 3D radiative MHD near-surface models of starspots with substantial penumbrae on cool main-sequence stars using the MURaM simulation code. This work is an improvement on the the previous starspot models in a slab…

Solar and Stellar Astrophysics · Physics 2025-01-29 Tanayveer Singh Bhatia , Mayukh Panja , Robert Cameron , Sami Solanki

Aims: The aim of this paper is to demonstrate that millimeter wave data can be used to distinguish between various atmospheric models of sunspots, whose temperature structure in the upper photosphere and chromosphere has been the source of…

Solar and Stellar Astrophysics · Physics 2015-01-14 Maria A. Loukitcheva , Sami K. Solanki , Stephen M. White

12 stable single sunspots were investigated in two aspects. The outer boundaries of the sunspots umbra were determined by an independent mathematical method and the vertical component of the magnetic field at these boundaries was found. We…

Solar and Stellar Astrophysics · Physics 2021-01-29 V. Efremov , L. Parfinenko , A. Soloviev

Stellar magnetic fields are produced by a magnetohydrodynamic dynamo mechanism working in their interior -- which relies on the interaction between plasma flows and magnetic fields. The Sun, being a well-observed star, offers an unique…

Solar and Stellar Astrophysics · Physics 2015-06-03 Dibyendu Nandy

The record of solar activity is reviewed here with emphasis on peculiarities. Since sunspot positions tell us a lot more about the solar dynamo than the various global sunspot numbers, we first focus on the records of telescopic…

Solar and Stellar Astrophysics · Physics 2015-06-22 R. Arlt , N. Weiss

The aim of the present study is to show the varying asymmetries during the decay of sunspot groups. The source of input data is the SoHO/MDI-Debrecen Database (SDD) sunspot catalog that contains the magnetic polarity data for time interval…

Solar and Stellar Astrophysics · Physics 2022-02-02 Judit Muraközy