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تسجيل مستخدم جديدOn the inhomogeneities of the sunspot penumbra
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The penumbra is ideally suited to challenge our understanding of magnetohydrodynamics. The energy transport takes place as magnetoconvection in inclined magnetic fields under the effect of strong radiative cooling at the surface. The relevant processes happen at small spatial scales. In this contribution we describe and elaborate on these small-scale inhomogeneities of a sunspot penumbra. We describe the penumbral properties inferred from imaging, spectroscopic and spectropolarimetric data, and discuss the question of how these observations can be understood in terms of proposed models and theoretical concepts.
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We describe the disappearance of a sector of sunspot penumbra and its restoring process observed in the preceding sunspot of active region NOAA 12348. The evolution of the magnetic field and the plasma flows support the idea that the penumbra forms d
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