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Figure 1:
A scheme of the method of MHD coronal seismology. |
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Figure 2:
A magnetic flux tube of radius |
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Figure 3:
Dispersion diagram showing the real phase speed solutions of dispersion relation (7 |
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Figure 4:
Transverse and longitudinal density perturbation (shown as intensity) and velocity structure (shown as a vector field) of a homogeneous magnetic cylinder model of a coronal loop, perturbed by a fundamental fast kink oscillation (from Resource 1). |
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Figure 5:
A magnetic flux tube of radius |
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Figure 6:
Radial profile of the Alfvén frequency in a loop with a thin edge layer of width |
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Figure 7:
Comparison of the dissipative decay of Alfvén waves in 1D plasma inhomogeneities with Alfvén speed profiles of different steepness. The solid curve shows the dissipative decay of Alfvén waves in an homogeneous plasma. Phase-mixing is therefore absent and the damping time is proportional to |
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Figure 8:
Symmetric Epstein density profiles of the form |
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Figure 9:
Comparison of group speeds of a propagating sausage mode guided by a 1D plasma inhomogeneity with the Alfvén speed contrast ratio of |
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Figure 10:
The temporal evolution of the loop displacement as an average coordinate of the loop position for four neighbouring, perpendicular cuts through the loop apex (diamonds), with error bars ( |
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Figure 11:
Light curves of the second burst (scaled arbitrarily). From top to bottom: Radio brightness temperature observed at |
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Figure 12:
The magnetic field inside a coronal loop as function of plasma density inside the loop, determined by Equation (32 |
| Figure 13:
Observationally determined loop oscillation decay times as a function of wavelength (left) and period (right) from: Nakariakov et al. (1999) and Aschwanden et al. (2002) ( |
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Figure 14:
Doppler oscillation events in the Fe XIX line observed with the SUMER instrument on 9 March 2001. a) Doppler shift time series. The redshift is represented with the bright colour, and the blueshift with the dark colour. b) Average time profiles of Doppler shifts along cuts AC and BD. The thick solid curves are the best fit functions of the form |
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Figure 15:
A typical response of a 1D loop to the flaring heat deposition near the apex. The density curve demonstrates pronounced quasi-periodic pulsations associated with the second standing acoustic harmonics. |
| Figure 16:
The sketch of the coronal loop model suggested by Tsiklauri and Nakariakov (2001). A coronal loop is considered as a magnetic field line with density and gravitational acceleration varying along the axis of the cylinder. |
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Figure 17:
The comparison of the theoretically predicted (the continuous curve) and observed amplitudes of the upwardly propagating EUV disturbances observed in polar plumes (from Ofman et al., 1999). |
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Figure 18:
Simultaneous time-distance plots of propagating EUV disturbances observed by TRACE in the 171 Å and 195 Å bandpasses along a slit. The distance along the slit is shown in opposite directions to demonstrate that the disturbances observed in different bandpasses form a “fishbone” structure (from King et al., 2003). |
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Figure 19:
Six upper panels (loops A - F): Evolution of correlation coefficients of propagating disturbances observed simultaneously in 171 Å and 195 Å bandpasses with the distance along six different slits. The solid lines show the correlation of unfiltered data while the dashed lines show the correlation of the signals after subtraction of slower variation. The dotted lines are the best-fitted straight lines. Two lower panels: Evolution of correlation coefficients of simulated signals. The left panel shows the correlation for the same angle with the line of sight, but for different temperatures |
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Figure 20:
A plot of the maximum amplitude at the most frequent scale of the points, analysed by Williams et al. (2001), against their loop position. The |
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Figure 21:
Numerical simulation of an impulsively generated fast magnetoacoustic wave train propagating along a coronal loop with a density contrast ratio of |
| Figure 22:
Left: TRACE 195 Å field of view on 21 April 2002 at 01:49:57 UT. The square gives the location of the subfield used in the data analysis. The subfield data cube has spatial coordinates |
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Figure 23:
Characterisation of the transverse displacement of a wave packet in edge B (see middle panel in Figure 22). Left: Transverse displacement as a function of |
| http://www.livingreviews.org/lrsp-2005-3 |
© Max Planck Society and the author(s)
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