λ 5303 Fe XIV density models of the inner solar corona

✍ Scribed by R. R. Fisher

• Publisher: Springer
• Year: 1978
• Tongue: English
• Weight: 580 KB
• Volume: 57
• Category: Article
• ISSN: 0038-0938
• DOI: 10.1007/bf00152049

✦ Synopsis

The Sacramento Peak Observatory's 40 cm coronagraph was used with an emission line photometer to observe the distribution of A5303 Fe xIv brightness as a function of position angle, height above the limb, and time. These data were used to construct models of the Volume emissivity as a function of solar latitude and longitude. These models in turn yield estimates of the distribution of electron density in the lower solar corona as a function of latitude and longitude for several specific periods in 1973 and 1975. Three observational results are obtained. An upper limit for the inferred electron density in coronal hole regions is set at log N, = 7.4 for an altitude of 1.15R~. Density models from late 1973 demonstrate an evolutionary trend toward a rather regular four-lobed appearance of coronal material; models from 1975 suggest that this characterization persisted for at least 27 solar rotations. A decrease in the total integrated A 5303 intensity of a factor of 2.9 is inferred to have taken place between 1973 and 1975.