On the color of the 26 February 1981 white light flare
Abstract
We describe visual observations of a white light flare which displayed a pink color in a part of the flare which covered a sunspot umbra. We then show that visible pink tint, if attributable to strong Hα emission, requires a minimum equivalent emission line width of approximately 140 A, or three times larger than in any flare previously measured. Such extreme line broadening might be interpreted to result from flare penetration to unusually high chromospheric densities (≳ 1014 cm−3), or from anomalous Stark broadening due to turbulent electric fields in an unstable plasma (Spicer and Davis, 1975) at lower density.
- Publication:
-
Solar Physics
- Pub Date:
- June 1982
- DOI:
- 10.1007/BF00151605
- Bibcode:
- 1982SoPh...78..225N
- Keywords:
-
- H Alpha Line;
- Solar Flares;
- Spectral Line Width;
- Stellar Color;
- Chromosphere;
- Solar Spectra;
- Stark Effect;
- Solar Physics;
- Color;
- Flare;
- Line Width;
- Emission Line;
- Visual Observation