Franz Kneer

TL;DR: The 1.5 m telescope GREGOR as discussed by the authors is Europe's largest solar telescope and number 3 in the world, with an all-reflective Gregory design that provides a large wavelength coverage from the near UV up to at least 5 microns, and is equipped with a high-order adaptive optics system, with a subaperture size of 10 cm and a deformable mirror with 256 actuators.

TL;DR: In this paper, a Fabry-Perot spectrometer was used to scan the two Fe I lines at 6301.5 and 6302.5 A. Magnetic signals occur predominantly in intergranular spaces.

TL;DR: In this article, a time sequence of Inter-Network (IN) magnetograms observed at the solar disk center is analyzed, showing that the magnetic structures producing the polarization have intrinsic field strengths exceeding 1 kG, and therefore occupying only a very small fraction of the surface.

TL;DR: In this article, a second narrow-band etalon and a full Stokes polarimeter based on ferroelectric liquid crystals were implemented in the two-dimensional "Gottingen" Fabry-Perot spectrometer/polarimeter at the Vacuum Tower Telescope, Observatorio del Teide/Tenerife.

TL;DR: In this article, a time sequence of Inter-Network (IN) magnetograms observed at the solar disk center was analyzed, showing that the magnetic signals changing in time scales smaller than 1 min, and a persistent pattern lasting longer than the duration of the sequence (17 min).