HARD X-RAY SOLAR FLARES REVEALED WITH YOHKOH HXT ―A REVIEW

摘要

Yohkoh/HXT has detected more than 2500 solar flares over its 10 years of operation. In the first five years of operation HXT has provided us with a lot of new information on solar flares. Some of its major achievements are providing both statistical and detailed event studies of double footpoint sources, the discovery of the above-the-looptop source as evidence for magnetic reconnection, and revealing characteristics of a super-hot (> 30 MK) thermal component. These results clearly indicate that many types of hard X-ray sources exist simultaneously even in a single flare. Flares, especially intense flares, which occurred during the current solar cycle, have been analyzed and many new results have been reported recently. They are summarized in this paper.