Spectropolarimetric investigations of the deep photospheric layers of solar magnetic structures / Nilda Oklay

Solar surface magnetism manifests itself in a variety of structures with sizes often comparable or even below the spatial resolution capabilities of modern telescopes. Nevertheless, information on the intrinsic atmospheric structure of even unresolved magnetic features can be obtained via appropriate choice of diagnostic tools and the use of spectropolarimetric data. The observed polarization signal can be analyzed with special methods to extract the physical parameters of the atmosphere. The main aim of this work is to investigate the temperature structure of the small scale magnetic elements and to expand our knowledge about the physics of the unresolved magnetic features of the deep photosphere. In order to achieve this aim, we used spectropolarimetric observations in carefully selected photospheric lines (including C I line as well as strong lines of Ti II and Fe I) covering also the deep layers of the photosphere. We obtained ratios of their Stokes V amplitudes in order to use them as a temperature diagnostic tool. Then we analyzed the measured profiles with inversions to obtain the temperature stratification along the line-of-sight. The resulting Stokes V amplitude values of the synthetic profiles are then compared to the measured ones. Afterwards, we computed synthetic observables of the spectral lines using snapshots from 3 D MHD simulations of the solar photosphere with varying magnetic activity. The obtained results are then compared with the results of the inversions. This is an exploratory work using Stokes V amplitude ratio technique in combination with inversions as well as numerical simulations to demonstrate the diagnostic potential of the proposed method.