Simultaneous polarimetric observations with VTT and THEMIS
Résumé
Spectro-polarimetric observations of sunspot groups have been performed simultaneously with the VTT and with THEMIS. At the VTT we observed a group of iron and silicon lines at 1078 nm with the Tenerife Infrared Polarimeter, and at THEMIS we observed in five spectral channels (MTRmode): Fe 630 nm, Na D, Hα, Fe 557.6 nm and alternatively Cr 578 nm or Fe 525 nm. The inversion of the Stokes-profiles was done with the SIR-code for the infrared lines and for Fe 630 nm, for the other spectral ranges the inversion is still pending. So far we derived that the magnetic field strength decreases with height at most locations inside the spots, in contrast to some recently published results of other investigations.