Abstract
During the summer and fall of 1971, Doppler spectroheliograms were obtained for several sunspots located near the solar limb. These observations confirm a previous result based on the study of only a few sunspots that in the plage-free photosphere surrounding sunspots the spatially-averaged, horizontal flow tends to be outward at 0.5–1.0 km s−1 for distances typically 10000–20000 km beyond the outer boundary of the penumbra. It is suggested that these material motions are the means by which small-scale fragments of magnetic flux are carried away from sunspots.
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References
Harvey, K. and Harvey, J. W.: 1972, (in preparation).
Harvey, K. L., Kulander, J. L., Martin, S. F., and Ramsey, H. E.: 1971, Lockheed Solar Observatory Report, LMSC D24368.
Leighton, R. B., Noyes, R. W., and Simon, G. W.: 1962, Astrophys. J. 135, 474.
Sheeley, Jr., N. R.: 1969, Solar Phys. 9, 347.
Sheeley Jr., N. R.: 1971, in R. Howard (ed.), ‘Solar Magnetic Fields’, IAU Symp. 43, 310.
Sheeley, Jr., N. R., and Bhatnagar, A.: 1971, Solar Phys. 19, 338.
Simon, G. W. and Leighton, R. B.: 1964, Astrophys. J. 140, 1146.
Vrabec, D.: 1971, in R. Howard (ed.), ‘Solar Magnetic Fields’, IAU Symp. 43, 329.
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Sheeley, N.R. Observations of the horizontal velocity field surrounding sunspots. Sol Phys 25, 98–103 (1972). https://doi.org/10.1007/BF00155747
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DOI: https://doi.org/10.1007/BF00155747