MHD seismology of the solar corona with SOHO and TRACE
UNSPECIFIED (2001) MHD seismology of the solar corona with SOHO and TRACE. In: 24th General Assembly of the International-Astronomical-Union, MANCHESTER, ENGLAND, AUG 07-18, 2000. Published in: RECENT INSIGHTS INTO THE PHYSICS OF THE SUN AND HELIOSPHERE: HIGHLIGHTS FROM SOHO AND OTHER SPACE MISSIONS (203). pp. 353-355.Full text not available from this repository.
Recent discoveries of MHD wave motions in the solar corona done with EUV imaging telescopes onboard SOHO and TRACE provide an observational basis for the MHD seismology of the corona. Measuring the properties of MHD waves and oscillations (periods, wavelengths, amplitudes, temporal and spatial signatures), combined with theoretical modeling of the wave phenomena, allow us to determine values of the mean parameters of the corona (the magnetic field strength, transport coefficients, etc.). As an example, we consider post-flare decaying oscillations of loops, observed with TRACE (14th July 1998 at 12:55 UT). An analysis of the oscillations shows that they are quasi-harmonic, with a period of about 265 s, and quickly decaying with the decay time of about 14.5 min. The period of oscillations allows us to determine the Alfven speed in the oscillating loop about 770 km/s. This value can be used for deduction of the value of the magnetic field in the loop (giving 10-30 G). The decay time, in the assumption that the decay is caused by viscous (or resistive) dissipation, gives us the Reynolds number of 10(5.3-6.1) (or the Lundquist number of 10(5.0-5.8)).
|Item Type:||Conference Item (UNSPECIFIED)|
|Subjects:||Q Science > QB Astronomy|
|Series Name:||IAU SYMPOSIA|
|Journal or Publication Title:||RECENT INSIGHTS INTO THE PHYSICS OF THE SUN AND HELIOSPHERE: HIGHLIGHTS FROM SOHO AND OTHER SPACE MISSIONS|
|Publisher:||ASTRONOMICAL SOC PACIFIC|
|Editor:||Brekke, P and Fleck, B and Gurman, JB|
|Number of Pages:||3|
|Page Range:||pp. 353-355|
|Title of Event:||24th General Assembly of the International-Astronomical-Union|
|Location of Event:||MANCHESTER, ENGLAND|
|Date(s) of Event:||AUG 07-18, 2000|
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