ON THE PROBLEM OF THE RELATIONSHIP BETWEEN SOLAR-FLARES AND CORONAL MASS EJECTIONS

Combination of SMM data with Mauna Loa and GOES measurements shows sig nificant relationships between coronal mass ejections (CMEs) and solar flares, or, more precisely, long decay (duration) X-ray events (LDEs) . This relationship is not understood in all its details. Although mas s ejections are considered to be a more probable candidate for the rol e of a driver, there is a problem, namely, which of these two phenomen a is cause and which is consequence. To understand this, one tradition ally compares start times of CMEs and LDEs. We show that the study of the correlation between XUV line broadening and the origin of CME acce leration gives additional possibilities to solve this problem. In the EUV emission, such investigations might possibly be carried out in the framework of the SOHO program. In the soft X-rays, SMM and Yohkoh dat a are convenient, albeit not for the same event.