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The center-to-limb variation of the photospheric wave spectrum

✍ Scribed by M. Stix; H. Wöhl

Publisher
Springer
Year
1974
Tongue
English
Weight
696 KB
Volume
37
Category
Article
ISSN
0038-0938

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✦ Synopsis

Using photoelectric observations in the Fe 5576/~ line we obtained line-of-sight velocities at nine different positions on the solar disk, as functions of one horizontal co-ordinate and time. With the help of the Fast Fourier Transform algorithm we calculated two-dimensional power spectra (horizontal wave number and frequency). Special attention was given to the possible existence of horizontal sound waves. We find only very little power in these waves; thus the excitation of the solar atmosphere to oscillations by locally overshooting granules, which should be accompanied by horizontal sound waves with large amplitudes, can play only a minor role.

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