Discussion on Line Formation and Photospheric Structure

Abstract

Areas on the photometric tracing enclosed by line profiles and an artificially truncated continuous level is studied. With these areas (fictitious equivalent widths), fictitious curves of growth can be constructed either theoretically or empirically. From the vertical and the horizontal shift between the theoretical and empirical curves, the Doppler width and the population of atoms are estimated for each truncated continuous level. Thus, the depth dependence of the Doppler width can be obtained empirically. For the solar photosphere, the result shows good agreement with the earlier determination by Unno.