Study of photospheric and chromospheric dynamics using high resolution spectropolarimetric observations

We present the results obtained from the recent observing campaigns performed at the Dunn Solar Telescope (NSO) dedicated to the study of the interplay between plasma and magnetic field in the lower layers of the solar atmosphere. Using high resolution spectro-polarimetric datasets taken by the Interferometric BIdimensional Spectropolarimeter (IBIS) we found some new details about the sunspot dynamics and the magnetic properties of their features. The inversion of the Stokes profiles of the Fe I 617.3 nm line and of the Fe I 630.25 nm line allowed us to provide new constraints for improving the modelling of the processes leading to the evolution of sunspots (Romano et al. 2013, ApJL 771 3; Romano et al. 2014, ApJ 784 10). Moreover, we deduced some interesting results from the comparison of the photospheric lines with the chromospheric spectral data taken along the Ca II 854.2 nm line and the Halpha 656.3 nm line: many properties of the plasma flow in photosphere seem to be influenced by the overlying configuration of the magnetic field in the chromosphere. The coordinated observations with space-based instruments (IRIS, SDO) were useful to describe the global evolution of the targets, with a wider observation time interval and a complementary vision of the magnetic systems visible in the corona.
This research work has received funding from the European Commissions Seventh Framework Programme under the grant agreements no. 312495 (SOLARNET project) and no. 606862 (F-Chroma project). This research is also supported by the ITA MIUR-PRIN grant on "The active sun and its effects on space and Earth climate".