Infrared lines as probes of solar magnetic features. IV - Discovery of a siphon flow
Abstract
Spectra of two neighboring IR lines, Fe I 15648.5 A and Fe I 15652.9 A, are analyzed. The spectra were obtained with an IR array detector in active region plages with the entrance slit of the spectrograph placed across the polarity-inversion (neutral) line. Near the neutral line the positive polarity field is weaker (about 1200 G) and shows an upflow of up to 2 km/s, while the negative polarity field is stronger (about 1500 G) and exhibits a downflow of up to 1 km/s. This configuration corresponds to the expected signature of a siphon flow along a loop connecting flux tubes across the neutral line.
- Publication:
-
Astronomy and Astrophysics
- Pub Date:
- August 1992
- Bibcode:
- 1992A&A...261L..21R
- Keywords:
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- Infrared Spectra;
- Solar Magnetic Field;
- Iron;
- Solar Spectra;
- Solar Physics