An analysis has been carried out of the center-to-limb variation of the apparent sizes of the umbra, penumbra, and whole spot. It has revealed that the umbral...

We present a time-dependent semiempirical model of the chromospheric umbral oscillation in sunspots. This model has been obtained by applying recently developed...

Context. The various mechanisms of magneto-convective energy transport determine the structure of sunspots and active regions. Aims: We characterise the...

We estimate the morphology of near-side active regions using near-side helioseismology. Active regions from two data sets, Air Force Data Assimilative...

Magnetohydrodynamic (MHD) simulations of the solar atmosphere are often performed under the assumption that the plasma is fully ionized. However, in the lower...

Context. The penumbra of sunspots has a complex magnetic field topology whose three-dimensional organization remains unclear after more than a century of...

This paper presents a detailed description, analysis, and interpretation of the spectropolarimetric observations recently reported by Socas-Navarro, Trujillo...

The usually assumed identification of small-scale magnetic concentrations with bright facular or network points on the photosphere is observationally checked by...

Fibrils are thin elongated features visible in the solar chromosphere in and around magnetized regions. Because of their visual appearance, they have been...