Journal ArticleDOI
Wave propagation in a magnetic cylinder
P. M. Edwin,B. Roberts +1 more
TLDR
In this article, the authors investigated the nature of oscillations in a magnetic cylinder embedded in magnetic environment and showed that the standard slender flux tube analysis of a kink mode in a cylinder excludes the possibility of a second mode, which arises under photospheric conditions.Abstract:
The nature of oscillations in a magnetic cylinder embedded in a magnetic environment is investigated. It is shown that the standard slender flux tube analysis of a kink mode in a cylinder excludes the possibility of a second mode, which arises under photospheric conditions. Under coronal conditions, two widely separated classes of oscillation can be freely sustained, one on an acoustic time-scale and the other on an Alfvenic time-scale. The acoustic-type oscillations are always present, but the much shorter period, Alfvenic-type, oscillations arise only in high density (strictly, low Alfven velocity) loops. An application to waves in fibrils is also given, and suggests (following Wentzel, 1979) that they are fast kink waves propagating in a density enhancement.read more
Citations
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Journal ArticleDOI
WAVES AND OSCILLATIONS IN THE CORONA (Invited Review)
TL;DR: In this article, the authors review theoretical aspects of how MHD waves and oscillations may occur in a coronal medium, and consider the various ways this may be brought about, and its implications for coronal heating.
Journal ArticleDOI
Characteristics of transverse oscillations in a coronal loop arcade
TL;DR: In this article, the authors investigated transverse oscillations in coronal loops of a post-flare loop arcade and deduced oscillation signatures such as displacement amplitude, period, phase and damping time.
Journal ArticleDOI
Doppler Shift Oscillations of Hot Solar Coronal Plasma Seen by SUMER: A Signature of Loop Oscillations?
TL;DR: The Doppler oscillations have periods of 14-18 minutes, with an exponential decay time of 12-19 minutes, and show an initial large blueshift pulse with peak velocities up to 77 km s-1.1 as mentioned in this paper.
Journal ArticleDOI
Determination of the Coronal Density Stratification from the Observation of Harmonic Coronal Loop Oscillations
TL;DR: In this paper, it was shown that the ratio of the period of the fundamental mode to the periods of the overtone mode differs from 2 in loops with longitudinal density stratification, which can be used as a seismological tool to obtain information about the density scale height in loops.
Journal ArticleDOI
Resonant MHD Waves in the Solar Atmosphere
TL;DR: In this paper, a review of the linear theory of MHD resonant waves in inhomogeneous plasmas is presented, where the authors discuss the properties of driven resonant MHD waves.
References
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Journal ArticleDOI
Elastic Waves in Layered Media
TL;DR: In this paper, Elastic Waves in Layered Media (ELMW) are used to describe the properties of layered media in a geologiska foreningen i Stockholm Forhandlingar.
Journal ArticleDOI
Wave propagation in a magnetically structured atmosphere
TL;DR: In this paper, the authors investigate the occurrence of magnetoacoustic surface waves at a single magnetic interface and consider in detail the case where one side of the interface is field-free.
Journal ArticleDOI
Wave propagation in a magnetically structured atmosphere: III: The slab in a magnetic environment
P.M. Edwin,B. Roberts +1 more
TL;DR: In this paper, the propagation of waves in a magnetic slab embedded in magnetic environment is investigated and possible modes of propagation are examined from the general dispersion relation, both analytically and numerically, for disturbances which are evanescent in the environment.