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Related papers: Radiative MHD simulation of sunspot structure

200 papers

Recently, there have been some reports of unusually strong photospheric magnetic fields (which can reach values of over 7 kG) inferred from Hinode SOT/SP sunspot observations within penumbral regions. These superstrong penumbral fields are…

Solar and Stellar Astrophysics · Physics 2019-10-30 A. Siu-Tapia , A. Lagg , M. van Noort , M. Rempel , S. K. Solanki

The long term study of the Sun is necessary if we are to determine the evolution of sunspot properties and thereby inform modeling of the solar dynamo, particularly on scales of a solar cycle. We aim to determine a number of sunspot…

Solar and Stellar Astrophysics · Physics 2011-08-23 Fraser T. Watson , Lyndsay Fletcher , Stephen Marshall

The umbral regions of sunspots and pores in the solar photosphere are generally dominated by $3$~mHz oscillations, which are due to $p$-modes penetrating the magnetic region. In these locations, wave power is also significantly reduced with…

We have carried out a 3D ideal-MHD (Magnetohydrodynamic) simulation to study the evolution of laser generated plasma plume in a moderate external magnetic field (0.13 T) oriented perpendicular to the flow direction of the plasma plume. The…

Plasma Physics · Physics 2021-10-27 Bhavesh G. Patel , Narayan Behera , R. K. Singh , Ajai Kumar , Amita Das

We used the flux calibrated images through the Broad Band Filter Imager and Stokes Polarimeter data obtained with the Solar Optical Telescope onboard the Hinode spacecraft to study the properties of bright points in and around the sunspots.…

Solar and Stellar Astrophysics · Physics 2015-05-18 Debi Prasad Choudhary , Toshifumi Shimizu

The magnetic field of a sunspot guides magnetohydrodynamic waves toward higher atmospheric layers. In the upper photosphere and lower chromosphere, wave modes with periods longer than the acoustic cut-off period become evanescent. The…

Solar and Stellar Astrophysics · Physics 2016-12-07 J. Löhner-Böttcher , N. Bello González , W. Schmidt

We use high spatial and spectral resolution observations obtained with the CRisp Imaging SpectroPolarimeter at the Swedish 1-m Solar Telescope to analyze the velocity profile of granular light bridges in a sunspot. We find upflows…

Solar and Stellar Astrophysics · Physics 2015-05-19 L. Rouppe van der Voort , L. R. Bellot Rubio , A. Ortiz

A three-dimensional (3D) MHD model is applied to simulate the evolution of a large-scale magnetic field in a barred galaxy possessing a gaseous halo extending to about 2.8 kpc above the galactic plane. As the model input we use a…

Astrophysics · Physics 2009-11-07 K. Otmianowska-Mazur , D. Elstner , M. Soida , M. Urbanik

We investigate the vertical gradient of the magnetic field of sunspots in the photospheric layer. Independent observations were obtained with the SOT/SP onboard the Hinode spacecraft and with the TIP-2 mounted at the VTT. We apply…

Solar and Stellar Astrophysics · Physics 2017-03-01 Jayant Joshi , Andreas Lagg , Johann Hirzberger , Sami K. Solanki , Sanjiv K. Tiwari

Measurements of maximum magnetic flux, minimum intensity, and size are presented for 12 967 sunspot umbrae detected on the NASA/NSO spectromagnetograms between 1993 and 2004 to study umbral structure and strength during the solar cycle. The…

Solar and Stellar Astrophysics · Physics 2011-04-07 T. A. Schad , M. J. Penn

We study the structure and reveal the physical nature of the reversed granulation pattern in the solar photosphere by means of 3-dimensional radiative hydrodynamics simulations. We used the MURaM code to obtain a realistic model of the…

Astrophysics · Physics 2009-11-11 M. C. C. Cheung , M. Schuessler , F. Moreno-Insertis

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

Sunspots survive on the solar surface for time-scales ranging from days to months. This requires them to be in an equilibrium involving magnetic fields and hydrodynamic forces. Unfortunately, theoretical models of sunspot equilibrium are…

Solar and Stellar Astrophysics · Physics 2025-07-09 J. M. Borrero , A. Pastor Yabar , M. Schmassmann , M. Rempel , M. van Noort , M. Collados

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

We applied automatic identification of sunspot umbrae and penumbrae to daily observations from the Helioseismic Magnetic Imager (HMI) on board the Solar Dynamics Observatory (SDO) to study their magnetic flux (B) and area (A). The results…

Solar and Stellar Astrophysics · Physics 2013-09-03 Andrey G. Tlatov , Alexei A. Pevtsov

Changes in the solar surface area covered by small-scale magnetic elements are thought to cause long-term changes in the solar spectral irradiance, which are important for determining the impact on Earth's climate. To study the effect of…

Solar and Stellar Astrophysics · Physics 2015-05-20 N. Afram , Y. C. Unruh , S. K. Solanki , M. Schuessler , A. Lagg , A. Voegler

The aim of this research is to simulate the interaction of the solar wind with the magnetic field of Mercury and to study the particle fluxes between the magnetosheath and the planet surface. We simulate the magnetosphere structure using…

Earth and Planetary Astrophysics · Physics 2016-08-17 J. Varela , F. Pantellini , M. Moncuquet

Aims. To understand the morphology of the chromosphere in sunspot umbra. We investigate if the horizontal structures observed in the spectral core of the Ca II H line are ephemeral visuals caused by the shock dynamics of more stable…

Solar and Stellar Astrophysics · Physics 2015-02-11 V. M. J. Henriques , E. Scullion , M. Mathioudakis , D. Kiselman , P. T. Gallagher , F. P. Keenan

We investigate the interaction of magneto-acoustic waves with magnetic network elements with the aim of finding possible signatures of the magnetic shadow phenomenon in the vicinity of network elements. We carried out three-dimensional…

Solar and Stellar Astrophysics · Physics 2015-06-05 C. Nutto , O. Steiner , M. Roth

$Context$. The thermal structure of the penumbra below its visible surface (i.e., $\tau_5 \ge 1$) has important implications for our present understanding of sunspots and their penumbrae: their brightness and energy transport, mode…

Solar and Stellar Astrophysics · Physics 2017-05-24 J. M. Borrero , M. Franz , R. Schlichenmaier , M. Collados , A. Asensio Ramos