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The purpose of this paper is to analyze the variation in the line width with height in the inner corona (region above 1.1 Rsun), by using the spectral data from LASCO-C1 aboard SOHO. We used data acquired at activity minimum (August - October 1996) and during the ascending phase of the solar cycle (March 1998). Series of images acquired at different wavelengths across the Fe X 637.6 nm (red) and Fe XIV 530.3 nm (green) coronal lines by LASCO-C1 allowed us to build radiance and width maps of the off-limb solar corona. In 1996, the line width of Fe XIV was roughly constant or increased with height up to around 1.3 Rsun and then it decreased. The Fe X line width increased with height up to the point where the spectra were too noisy to allow line width measurements (around 1.3 Rsun). Fe X showed higher effective temperatures as compared with Fe XIV. In 1998 the line width of Fe XIV was roughly constant with height above the limb (no Fe X data available).
The nonthermal broadening of spectral lines formed in the solar corona is often used to seek the evidence of Alfven waves propagating in the corona. To have a better understanding of the variation of line widths at different altitudes, we measured th
Heavy ions are markers of the physical processes responsible for the density and temperature distribution throughout the fine scale magnetic structures that define the shape of the solar corona. One of their properties, whose empirical determination
The onset of the Rush to the Poles of polar-crown prominences and their associated coronal emission is a harbinger of solar maximum. Altrock (Solar Phys. 216, 343, 2003) showed that the Rush was well-observed at 1.15 Ro in the Fe XIV corona at the Sa
X-ray fluorescent lines are unique features of the reflection spectrum of the cold torus when irradiated by the central AGN. Their intrinsic line widths can be used to probe the line-emitting region. The line widths of the Fe Ka line measured from th
We have used an electron beam ion trap to measure electron-density-diagnostic line-intensity ratios for extreme ultraviolet lines from F XII, XIII, and XIV at wavelengths of 185-205 255-276 Angstroms. These ratios can be used as density diagnostics f