Issue |
A&A
Volume 486, Number 3, August II 2008
|
|
---|---|---|
Page(s) | 1015 - 1022 | |
Section | The Sun | |
DOI | https://doi.org/10.1051/0004-6361:200809626 | |
Published online | 04 June 2008 |
Effect of longitudinal magnetic and density inhomogeneity on transversal coronal loop oscillations
Solar Physics and Space Plasma Research Centre (SP2RC), University of Sheffield, Hicks Building, Hounsfield Road, Sheffield, S3 7RH, UK e-mail: [G.Verth;Robertus]@sheffield.ac.uk
Received:
21
February
2008
Accepted:
28
May
2008
Context. Observations of post-flare transversal coronal loop oscillations by TRACE have given us an excellent opportunity to implement magneto-seismological techniques for probing the plasma fine structure of the Sun's upper atmosphere.
Aims. We investigate the combined effect of magnetic and density stratification on transversal coronal loop oscillations.
Methods. A coronal loop will be modelled as an expanding magnetic flux tube with arbitrary longitudinal plasma density. The governing equation of the fast kink body mode is derived and solved by analytical approximation and numerical methods.
Results. It is found that even a relatively small coronal loop expansion can have a significant and pronounced effect on the accuracy of the plasma density scale height measurements derived from observation of loop oscillations.
Conclusions. To conduct more accurate and realistic magneto-seismology of coronal loops, the magnetic field divergence should be taken into account.
Key words: Sun: corona / Sun: magnetic fields / Sun: oscillations / Sun: fundamental parameters
© ESO, 2008
Current usage metrics show cumulative count of Article Views (full-text article views including HTML views, PDF and ePub downloads, according to the available data) and Abstracts Views on Vision4Press platform.
Data correspond to usage on the plateform after 2015. The current usage metrics is available 48-96 hours after online publication and is updated daily on week days.
Initial download of the metrics may take a while.