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We study the photospheric evolution of an exploding granule observed in the quiet Sun at high spatial (∼0.″3) and temporal (31.5 s) resolution by the imaging magnetograph Sunrise /IMaX in 2009 June. These observations show that the exploding granule is cospatial to a magnetic flux emergence event occurring at mesogranular scale (up to ∼12 Mm2 area). Using a modified version of the SIR code for inverting the IMaX spectropolarimetric measurements, we obtain information about the magnetic configuration of this photospheric feature. In particular, we find evidence of highly inclined emerging fields in the structure, carrying a magnetic flux content up to ∼4 × 1018 Mx. The balance between gas and magnetic pressure in the region of flux emergence, compared with a very quiet region of the Sun, indicates that the additional pressure carried by the emerging flux increases the total pressure by about 5% and appears to allow the granulation to be modified, as predicted by numerical simulations. The overall characteristics suggest that a multipolar structure emerges into the photosphere, resembling an almost horizontal flux sheet. This seems to be associated with exploding granules. Finally, we discuss the origin of such flux emergence events. [ABSTRACT FROM AUTHOR]

We investigate the dynamics and magnetic properties of orphan penumbrae observed in the solar photosphere to understand the formation process of such structures. We observed two orphan penumbrae in active region NOAA 11089 during a coordinated observing campaign carried out in 2010 July, involving the Hinode/Solar Optical Telescope (SOT) and Dutch Open Telescope (DOT), benefiting also from continuous observations acquired by the SDO satellite. We follow their evolution during about three days. The two structures form in different ways: one seems to break off the penumbra of a nearby sunspot, the other is formed through the emergence of new flux. Then they fragment while evolving. The SDO Helioseismic and Magnetic Imager measurements indicate the presence of strong line-of-sight motions in the regions occupied by these orphan penumbrae, lasting for several hours and decreasing with time. This is confirmed by SOT spectro-polarimetric measurements of the Fe I 630.2 nm pair. The latter also show that Stokes parameters exhibit significant asymmetries in the orphan penumbral regions, typical of an uncombed filamentary structure. The orphan penumbrae lie above polarity inversion lines, where peculiar plasma motions take place with velocities larger than ±3 km s–1. The vector magnetic field in these regions is highly inclined, with the average magnetic field strength decreasing with time. The DOT observations in the Hα line and SDO Atmospheric Imaging Assembly measurements in the He II 30.4 nm line indicate that there is no counterpart for the orphan penumbrae at midchromospheric heights or above. Our findings suggest that in at least one of the features investigated the emerging flux may be trapped in the low atmospheric layers by the overlying pre-existing fields, forming these filamentary structures. [ABSTRACT FROM AUTHOR]