The evolution of a rapidly-expanding active region loop into a trans-equatorial coronal mass ejection

Abstract

On 23 February 1997, a coronal mass ejection erupted off the NE limb of the sun from a coronal loop system which had earlier been visible soft X-rays and Fe XIV. The ejection coincided with the onset of a small soft X-ray event, and it left the corona at a position angle of around 60 deg at around 880 km s(exp -1). This ejection then merged with a much larger event which spanned the equator and became indistinguishable, in projection, with the primary event. The soft X-ray images indicate that the highest temperature plasma was associated with the loop system near the original erupting loop. A large loop system became visible south of the equator as the coronal mass ejection developed. It appears that there are high closed coronal magnetic loops linking the northern region to that in the south.