High-resolution photography of the solar chromosphere

✍ Scribed by R. J. Bray

• Publisher: Springer
• Year: 1973
• Tongue: English
• Weight: 689 KB
• Volume: 29
• Category: Article
• ISSN: 0038-0938
• DOI: 10.1007/bf00150809

✦ Synopsis

High-resolution filtergrams of the quiet chromosphere, taken at seven wavelengths in Ha with the aid of a computer-controlled ~ A filter, have been used to derive the contrast of ten bright and dark mottles as functions of wavelength. The contrast profiles of bright and dark mottles are strikingly different. They disagree with Athay's (1970) 'velocity' model but, with an appropriate choice of parameters, can be brought into good agreement with Beckers' (1964) 'cloud' model. Comparison between observation and theory yields values for the source function S, optical thickness to, line broadening parameter d20, and line-of-sight velocity V for both bright and dark mottles. The values of S and to obtained for dark mottles are consistent with Beckers' (1968) spicule model.