Kink and fluting modes of stratified coronal magnetic loops with elliptical cross-sections

Aims. We study kink and fluting oscillations of a straight magnetic tube with an elliptic cross-section and density varying along the tube. Methods. The governing equations for kink and fluting modes in the thin tube approximation are derived. We found that there are two kink modes, polarised along...

Full description

Saved in:
Bibliographic Details
Published in:Astronomy and astrophysics (Berlin) 2011-03, Vol.527, p.A53
Main Authors: Morton, R. J., Ruderman, M. S.
Format: Article
Language:English
Subjects:
Approximation
Astronomy
Coronal loops
Cross sections
Density
Earth, ocean, space
Exact sciences and technology
Grooving
magnetohydrodynamics (MHD)
Mathematical analysis
Oscillations
plasmas
Sun: corona
Sun: oscillations
Tubes
waves
Citations: Items that this one cites
Items that cite this one
Online Access:Get full text
Tags: Add Tag
No Tags, Be the first to tag this record!
Description
Summary:Aims. We study kink and fluting oscillations of a straight magnetic tube with an elliptic cross-section and density varying along the tube. Methods. The governing equations for kink and fluting modes in the thin tube approximation are derived. We found that there are two kink modes, polarised along the semimajor and semiminor axes of the elliptic cross-section. We have shown that the ratio of frequencies of the first overtone and fundamental mode is the same for both kink modes and independent of the ratio of the ellipse axes. Results. On the basis of this result we concluded that the estimates of the atmospheric scale height obtained using simultaneous observations of the fundamental mode and first overtone of the coronal loop kink oscillations are independent of the ellipticity of the loop cross-section.
ISSN:0004-6361
1432-0746
DOI:10.1051/0004-6361/201016028