Granulation In and Out of Magnetic Region. (Reannouncement with New Availability Information).

摘要

We performed an analysis of several granulation pictures obtained in both a quiet region and a plage or magnetic region. Filtergrams of ultra-narrow passband and free of line-blocking were obtained with the Sac Peak Vacuum Telescope with an average 0.5 arcsec spatial resolution. Results of a statistical comparative study are presented: amplitude spectra, RMS and histograms of intensity fluctuations. The precise location of a large sample of magnetic field structures identified with MgI b sub 1 + 0.4A filtergrams was analyzed; 20.4% of these structures overlap or are inserted in granules, which give a natural explanation of the high value of the RMS in the magnetic region. We used selected very high spatial resolution broad-band short exposure time pictures to show crinkles-type structures at the center of granules that we identify with the abnormal granulation and 'magnetic' granules.