Our investigation showed that the coupling between the regions in several cases was so efficient that at the instant of a flare in one of these regions the transient was detected near the other region. While the regions were on the east edge of the visible disk, there was no streamer near the region with a flare, and in the respective quadrant at all. In other words, the neutral field line of the source surface did not go through the position angle of this active region. When the region was near the west limb, the streamer either went very close to the pole (May 4, 6) or was absent in this quadrant (May 9). The neutral line of a global magnetic field is probably associated with the place where the transients usually leave the surface. It seems most likely that the quick transmission of influence from 8210 to 8214 is caused by electric currents of the magnetic loops. This problem should be studied in more detail. Our preliminary analysis leads to the conclusion that there are two mechanisms for the formation of transients detected in the C2, C3 field of view. The first mechanism: a spiral ejection with high velocities is generated in the active region; a transient, going into the interplanetary space, appears in the same place; the instability, producing the ejection, is transmitted approximately within one hour below the photosphere to the associated region in this complex of activity, where a transient is formed in a similar way; then, these transients interact with each other in the field of view of C3 (Mogilevskij et al. 1999). The second mechanism: the ejection appears at the site of an instability (i.e., a flare); the excitation is very quickly transmitted through the coronal loops to the place on the solar surface where the escape of transient is the easiest. Under favorable location of the region of generation, it simultaneously produces another transient. As a result, we get the concepts of the multiple CME (Dere et al.1998; Lyons et al. 1998).
Therefore, our consideration of a sequence of C2, C3 movies describing the
motion of regions with flares over the disk, shows that:
1) a CME can not only appear near the region of the generating instability but also near the site located at a distance of the order of one solar radius from that region. In this case, the influence is transmitted very quickly. The proximity of projection of the neutral line of the source surface field is favorable for the escape of transient;
2) interaction of structural objects of a transient can be followed by the generation of 1-8 A emission, whose instants coincide with maxima instants of the long duration burst in 1-8 A, commonly observed in considerable flares.
In addition it is shown that under favorable conditions for the escape from the surface, subflares may generate CME. The hypothesis of observation of intensive CME only from the regions localized within 40 degrees from the solar limb is confirmed. The presence (or absence) of burst in the range 1-8 A at the instant predicted for the appearance of the transient near the surface is the evidence that an event on the visible (or back) side of the Sun is responsible for the generation of the CME.
The author is very grateful to Dr. R. Howard for the possibility of using the C2, C3, 195 A movies via Internet.
This work was carried out by the financial support of the Russian Foundation for Basic Research (grants Nos. 96-02-16285, 96-02-16827a) and the Astronomy State Program.
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