2. Several Comments on Events of November 2004
[5] A very bright and broad loop front development was
documented by the SOHO/LASCO
C2 coronograph around
N09W17, with weak propagation to south. Full Halo was
formed at 1706 UT.
The first appearance of the ejecta in the field of view of
the LASCO/C3 coronograph occurred 1718 UT. The average
propagation velocity of the perturbation in the picture plane was
1460 km s-1. The initial interpretation by several observers
suggested an association exclusively with the dynamical
processes in only one the Active Region AR 10696 in the
northern hemisphere
[Panasyuk et al., 2004;
Yermolaev et al., 2005].
Such localization appeared to be not quite correct and to
be partially misleading because of obvious dynamical
connections with other active regions (ARs) 10695 and 10693 in
the southern hemisphere. In reality, a transequatorial
prominence was seen here in between active regions. It was
partially erupted.
|
Figure 1
|
[6] This observation provides the key and a clear indication
that strongest events in the heliosphere have a relation to the
evolution of the larger-scale structures and processes on the Sun,
transequatorial ones among them, and not only just one active
region as usually assumed a priori without sufficient
justifications. Moreover, according to our hypothesis, namely,
that these larger scales are providers of the needed free energy
for eruptive phenomena with their manifestations as flares and
CMEs
[Panasyuk et al., 2004;
Zhukov et al., 2004(available at http://www.congrex.nl/04c27/4)].
In the
November 2004 case,
multiple CMEs originated around the
central meridian and in the southwest part of the disk.
Corresponding electric and magnetic fields with electric currents
were responsible for this evolution. Several large dimmings
were seen in Extreme ultraviolet Imaging Telescope (EIT)
images here on 7 November around ARs 10696, 10695 and
10693. It is not just a projection effect but is also an indication
of the tight couplings in their evolution (Figure 1).
|
Figure 2
|
|
Figure 3
|
[7] Other evidence of the large-scale changes showing the
disappearance of the part of the very long transequatorial
filament (prominence) can be seen in Figure 2. Sequential
pictures were taken in the
H -alpha line at the
Kanzelhöhe
Solar
Observatory.
[8] The magnetic field in the corona was calculated by
G. V. Rudenko (http://bdm.iszf.irk.ru) in different approximations
using photospheric magnetograms for this period of time.
Results also clearly show large-scale loops connecting different
active regions (Figure 3). Long-distance nonlocal couplings are
possible via electric currents and heat fluxes along these loops.
![AGU](/journals/articleCitationLogo.gif)
Powered by TeXWeb (Win32, v.2.0).