COORDINATED OBSERVATION OF THE SOLAR CORONA USING THE NORIKURA CORONAGRAPH AND THE YOHKOH SOFT-X-RAY TELESCOPE

Spectroscopic observations of coronal emission lines were carried out at the Norikura Solar Observatory in cooperation with the soft X-ray telescope on board the Yohkoh satellite to study the plasma distributions at different temperatures. Intensity and velocity distributions in Fe XIV lambda 5303 (green), Fe X lambda 6374 (red), and Ca XV lambda 5694 (yellow) lines are compared with the soft X-ray images. It is found that the soft X-ray images closely resemble those of the yellow line that represents a rather high temperature component of the corona. On the other hand the low-temperature component seen in the green and the red lines shows quite a different distribution from that of the high-temperature component; the low-temperature component consists of many thin loops or streaks, while the high-temperature component is more diffuse. We fmd that the active elements of the cool component, i.e., complex loop systems, rapid changes of small structures, and localized large plasma motions, all tend to be cospatial with the hot component.