EDP Sciences
Free Access
Volume 432, Number 1, March II 2005
Page(s) 319 - 329
Section The Sun
DOI https://doi.org/10.1051/0004-6361:20041627

A&A 432, 319-329 (2005)
DOI: 10.1051/0004-6361:20041627

On small scale magnetic structures in the solar photosphere

S. Stangl and J. Hirzberger

Institut für Geophysik, Astrophysik und Meteorologie, Universitätsplatz 5, 8010 Graz, Austria
    e-mail: stefan.stangl@uni-graz.at

(Received 9 July 2004 / Accepted 3 November 2004)

The distribution of the magnetic field on the solar surface is as yet unknown in detail, but of considerable importance for solar physics in general. We have observed two different solar regions, one containing a small pore, the other region comprising a network in the light of the $\ion{Fe}{i}$ $\lambda6301.5\ \mbox\AA$ and $\ion{Fe}{i}$ $\lambda6302.5\ \mbox\AA$ lines at the German Vacuum Tower Telescope of the Observatorio del Teide (Tenerife, Spain) with the "Göttingen" Fabry-Pérot Interferometer. By applying image reconstruction techniques to broad- and narrowband filtergrams we obtained continuum images, line core images, as well as line-of-sight velocity and magnetic field maps. We present scatter plots of the line core intensity vs. the Doppler velocity and the vertical component of the magnetic field, which reveal that the line core brightness is not a clear indicator for magnetic fields in the solar atmosphere. Furthermore, we estimate the swaying motion of flux tubes to be mostly smaller than 0 $\farcs$3 and thus in good agreement with the predictions of theoretical dynamic models. Finally, we show how the choice of the observed solar target influences the results and their interpretation. We claim that generalizations can mislead, and strongly depend on the presence or absence of solar (magnetic) features in the analyzed data.

Key words: Sun: photosphere -- Sun: magnetic fields -- techniques: spectroscopic -- techniques: polarimetric

© ESO 2005