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Dynamical implications of Siivline profiles from OSO-8 observations

✍ Scribed by Donald E. Billings; Robert Roussel-Dupré; Michael H. Francis

Book ID
104644694
Publisher
Springer
Year
1977
Tongue
English
Weight
774 KB
Volume
55
Category
Article
ISSN
0038-0938

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✦ Synopsis

The widths and rms variations of line centers for h 1393 profiles from the Si IV ion in the solar transition zone, as observed by OSO-8, are analyzed to give the amplitudes and periods of three postulated types of disturbance: sinusoidal acoustic waves; sinusoidal acoustic shocks; and normally propagated MHD waves. All three assumptions lead to mean intervals between disturbances of 40-50 s, but acoustic waves and shocks are rules out because they predict intensifications of brightness far in excess of anything observed. MHD disturbances in magnetic fields ~2 G are consistent with observations, but normally propagated disturbances also give too great an intensification in brightness. Disturbances with wave vectors at an angle to the magnetic field are suggested.

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