The derivation of temperature gradient and electron density maps from EUV spectroheliograms

✍ Scribed by George L. Withbroe

• Publisher: Springer
• Year: 1972
• Tongue: English
• Weight: 987 KB
• Volume: 25
• Category: Article
• ISSN: 0038-0938
• DOI: 10.1007/bf00155750

✦ Synopsis

We discuss spatial variations in electron density at the base of the corona and in the temperature gradient in the chromospheric-coronal transition layer as determined from analysis of maps constructed from Mgx and Ovr spectroheliograms. Both the mapping techniques and results of analyzing EUV spectra from OSO 6 observations are presented. Comparisons of these maps with photospheric magnetograms and spectroheliograms made in chromospheric EUV lines and continua indicate that the electron density and temperature gradient in the transition layer tend to be enhanced in areas where the photospheric magnetic field and chromospheric EUV emission are enhanced. Relationships among the coronal electron density, transition-layer temperature gradient, chromospheric emission, and photospheric magnetic field strength are derived.