Bibcode
Luna, M.; Terradas, J.; Oliver, R.; Ballester, J. L.
Bibliographical reference
The Astrophysical Journal, Volume 692, Issue 2, pp. 1582-1589 (2009).
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2
2009
Journal
Citations
30
Refereed citations
30
Description
We study the collective kinklike normal modes of a system of several
cylindrical loops using the T-matrix theory. Loops that have similar
kink frequencies oscillate collectively with a frequency which is
slightly different from that of the individual kink mode. On the other
hand, if the kink frequency of a loop is different from that of the
others, it oscillates individually with its own frequency. Since the
individual kink frequency depends on the loop density but not on its
radius for typical 1 MK coronal loops, a coupling between kink
oscillations of neighboring loops takes place when they have similar
densities. The relevance of these results in the interpretation of the
oscillations studied by Schrijver & Brown in 2000 and Verwichte et
al. in 2004, in which transverse collective loop oscillations seem to be
detected, is discussed. In the first case, two loops oscillating in
antiphase are observed; interpreting this motion as a collective kink
mode suggests that their densities are roughly equal. In the second
case, there are almost three groups of tubes that oscillate with similar
periods, and therefore their dynamics can be collective, which again
seems to indicate that the loops of each group share a similar density.
All the other loops seem to oscillate individually and their densities
can be different from the rest.