Spatial variations of the Sr I 4607 Åscattering polarization signals at subgranular scale observed with ZIMPOL at the GREGOR telescope
Informazioni aggiuntive
Autori
Tipo
Articolo pubblicato in rivista scientifica
Anno
2019
Lingua
Inglese
Abstract
Sr I 4607 Åspectral line shows one of the strongest scattering polarization signals in the visible solar spectrum. The amplitudes of these signals are expected to vary at granular spatial scales. This variation can be due to changes in the magnetic field intensity and orientation (Hanle effect) as well as due to spatial and temporal variations in the plasma properties. Measuring the spatial variation of such polarization signal are challenging since both high spatial resolution and high spectropolarimetric sensitivity are required at the same time. To the aim of measuring these spatial variations at granular scale, we carried out a spectro-polarimetric measurement with the Zurich IMaging POLarimeter (ZIMPOL), at the GREGOR solar telescope at different limb distances on solar disk. Our results show a spatial variation of scattering linear polarization signals in Sr I 4607 Åline at the granular scale at every ensuremathmu, starting from 0.2 to 0.8. The correlation between the scattering linear polarization signal amplitude and the continuum intensity imply statistically that the scattering polarization is higher at the granular regions than in the intergranular lanes.
Rivista
Nuovo Cimento C Geophysics Space Physics C
Volume
42
Numero
1
Pagina inizio
6
Parole chiave
irsol-conference-proceedings
