Solar Physics DOI: 10.1007/---- Magnetic Field Structures in a Facular Region Observed by THEMIS and Hinode

Abstract The main objective of this paper is to build and compare vector magnetic maps obtained by two spectral polarimeters, i.e. THEMIS/MTR and Hinode SOT/SP, using two inversion codes (UNNOFIT and MELANIE) based on the Milne-Eddington solar atmosphere model. To this end, we used observa-tions of a facular region within active region NOAA 10996 on 23 May 2008, and found consistent results concerning the eld strength, azimuth and inclination distributions. Because SOT/SP is free from the seeing eect and has better spatial resolution, we were able to resolve small magnetic polarities with sizes of 100 to 200, and could detect strong horizontal magnetic elds, which converge or diverge in negative or positive facular polarities. These ndings support models which suggest existence of small vertical ux tube bundles in faculae. A new method is proposed to get the relative formation heights of the multi-lines ob-served by MTR assuming the validity of a ux tube model for the faculae. We found that the Fe i 6302.5 A line forms at a greater atmospheric height than the Fe i 5250.2 A line