THREE DIMENSIONAL CHROMOSPHERE THERMAL STRUCTURE OF SUNSPOT

Abstract:

We have observed sunspots using the Spectropolarimeter for infrared and optical wavelength ranges at the Dunn Solar Telescope during 29 July to 4 August 2013. The data consists of full Stokes profiles in the Ca II 854.2 nm and Fe I 1.56 micron lines. The inversion of these Stokes spectra provides the magnetic, thermal and velocity structure at photospheric and chromospheric heights of sunspots. In this contribution, we present the results on the 3D thermal structure in the super-penumbral canopy of a well rounded sunspot, derived by a novel approach for the inversion of Ca II IR spectra. Tracing individual fibrils in the super-penumbral canopy, we find that about half of them form only short loops of a a few Mm length that return to the photosphere in the close surroundings of the sunspot instead of connecting to more remote magnetic network at the outer end of the moat flow.