Analysis of EUV Observations of Regions of the Quiet and Active Corona at the Time of The 1970 March 7 Eclipse

A series of EUV spectra were obtained from a rocket flight during the 1970 March 7 total solar eclipse. The intensities of permitted and forbidden emission lines in both quiet and active regions have been analysed. The densities and temperatures have been derived as a function of position in the active region. In a given line-of-sight the density increases with increasing temperature and overall the central, low, parts of the active region contain more material at the higher temperatures than do the more extensive loop systems. The populations of the excited levels of the forbidden lines have been calculated using currently available atomic data. It appears that these and known excitation processes significantly underestimate the excited level populations. The populations used have therefore been normalized by using a quiet region of the corona as a diagnosed plasma.