Abstract
The Lyot Hα-heliograph at the Royal Observatory, Cape of Good Hope was in almost daily operation from March 12, 1958 to December 31, 1965. From the records obtained, a definitive list of 2907 flares was compiled, their properties analyzed, and the results presented herein.
The data on East-West distribution of activity, although inconclusive, shows an asymmetry of flare activity with 56.5% of the flares West of the central meridian; this is partially due, however, to an inhomogeneous density distribution in the filtergrams.
Flare distribution with respect to heliographic longitude, association with spot types and number of spots in the group are also discussed. The frequency of flare areas, rise times, and durations are examined as is their relationship to distance from the disk centre.
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Reid, J.H. Cape Lyot Hα-heliograph results. Sol Phys 5, 207–235 (1968). https://doi.org/10.1007/BF00147966
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DOI: https://doi.org/10.1007/BF00147966