Solar Limb Darkening 1986-1990 Lambda 303-NANOMETERS to 1099-NANOMETERS
Abstract
The Sun's limb darkening was observed repeatedly between the 1986 minimum and the 1990 maximum of solar activity.Systematic variations, which could depend either on the momentary activity and/or the phase in the solar cycle, werenot detectable, either at continuum wavelengths or in two broad-band spectral intervals. Completelyirregular variations, which concern not only individual, successive scans (due to granulation, etc.), but also thedaily andseasonal averages, are usually less than 1%, but can reach occasionally 2% or even more. Minoreast-west asymmetries even in the seasonal means seem to be well established, mainly for λ < 400 nm. Thefinal, mean limb-darkening coefficients agree basically with those published by Pierce and Slaughter (1977) and Pierce, Slaughter, and Weinberger (1977), but show a much lower scatter when plotted against wavelength.
- Publication:
-
Solar Physics
- Pub Date:
- August 1994
- DOI:
- 10.1007/BF00712494
- Bibcode:
- 1994SoPh..153...91N
- Keywords:
-
- Infrared Astronomy;
- Irradiance;
- Light (Visible Radiation);
- Light Scattering;
- Limb Darkening;
- Solar Cycles;
- Solar Limb;
- Ultraviolet Astronomy;
- Variations;
- Eureca (Esa);
- Nimbus 7 Satellite;
- Satellite-Borne Instruments;
- Solar Maximum Mission;
- Spacelab;
- Spectrographs;
- Upper Atmosphere Research Satellite (Uars);
- Solar Physics;
- Solar Phys;
- Disk Center;
- Solar Limb;
- Filter Channel;
- Continuum Wavelength