2D-spectroscopic observations of G-band bright structures
Abstract
We took two-dimensional spectra with the filter spectrometer TESOS at the German Vacuum Tower Telescope, Tenerife, of an absorption line of the CH-molecule and a Fe II-line in the G-band at 430.3 nm. We observed a region of granulation near a pore, close to disk center that showed many structures with enhanced G-band intensity. We introduce a Bright Point Index (BPI) defined by the ratio of the normalized line depressions of the Fe II and the CH-line. The BPI allows to characterize the bright structures by a quantity based on their spectroscopic signature. Bright structures, caused by significant weakening (up to 40% less absorption) of the absorption lines of the CH-molecule, have high BPI values and are accompanied by downflows. The remaining G-band bright structures, only caused by an enhanced continuum intensity, have low BPI and are related to granules.
- Publication:
-
Solar Variability: From Core to Outer Frontiers
- Pub Date:
- December 2002
- Bibcode:
- 2002ESASP.506..455L
- Keywords:
-
- Photosphere;
- Magnetic Elements