Context. Light bridges are bright, long, and narrow features that are typically connected to
the formation or decay processes of sunspots and pores. Aims. The interaction of magnetic …

Context. While it is conjectured that a chromospheric canopy plays a role in penumbra
formation, it has been difficult to find observational evidence of the connectivity between the …

We studied the variations of line of sight photospheric plasma flows during the formation
phase of the penumbra around a pore in active region NOAA 11490. We used a high spatial …

We studied the formation of the first penumbral sector around a pore in the following polarity
of the NOAA Active Region (AR) 11490. We used a high spatial, spectral, and temporal …

We investigate whether flux cancellation is responsible for the formation of a very massive
filament resulting in the spectacular eruption on 2011 June 7. We analyze and quantify the …

Context. We recently presented evidence that stable umbra-penumbra boundaries are
characterised by a distinct canonical value of the vertical component of the magnetic field, B …

Context. Fully fledged penumbrae have been widely studied both observationally and
theoretically. Yet the relatively fast process of penumbra formation has not been studied …

Context. The intermediate stages between pores and the formation of sunspots are a rare
phenomenon and can be manifested as transient photospheric penumbral-like filaments …

In this study, we investigate the decay of sunspots in the active region NOAA 13229 using
data from the ASO-S/FMG and SDO/HMI. We closely examine the decay patterns of …

Context. It has been reported that the boundary between the umbra and the penumbra of
sunspots occurs at a canonical value of the strength of the vertical magnetic field …