Structure of Sunspots. III: A Minimum-Gradient Model Atmosphere for Umbrae
Abstract
We present a minimum-gradient model to complement a maximum-gradient model (Zwaan, 1974). Both models are compatible with published continuum intensities and within constraints on the temperature gradient; both are adjusted to Teff=4000K. In order to explain the visual intensities the minimum-gradient model requires an additional `line-haze' opacity which is only slightly smaller than in the maximum-gradient model.
- Publication:
-
Solar Physics
- Pub Date:
- November 1975
- DOI:
- 10.1007/BF00152222
- Bibcode:
- 1975SoPh...45..115Z
- Keywords:
-
- Astronomical Models;
- Solar Atmosphere;
- Sunspots;
- Umbras;
- Absorption Spectra;
- Brightness Temperature;
- Hydrogen Ions;
- Line Spectra;
- Radiant Flux Density;
- Stellar Structure;
- Solar Physics;
- Temperature Gradient;
- Continuum Intensity;
- Published Model;
- Visual Intensity;
- Plausible Constraint