摘要: Investigation of the behavior of coronal intensity above the limb in Fe XIV emission (5303A) obtained at Sacramento Peak Observatory over the last fourteen years has resulted in the confirmation of a second set of zones of solar a... 展开 Investigation of the behavior of coronal intensity above the limb in Fe XIV emission (5303A) obtained at Sacramento Peak Observatory over the last fourteen years has resulted in the confirmation of a second set of zones of solar activity at high latitudes separate from the Main Activity Zones (MAZ). Localized emission peaks in Fe XIV 5303A are observed through most of the cycle at latitudes in individual daily scans, annual averages, and solar-cycle summary plots of the location of all local maximum intensities at 0.15R above the limb. These peaks evolve slowly over a period of days, consistent with the rotation over the limb of stable features, in a similar way to the lower-latitude peaks that are connected with active regions. The high-latitude coronal activity zones first appear at latitudes of 70 to 80 deg, 2-3 years after solar minimum. They evolve approximately parallel to the MAZ, with the average latitude decreasing at rate of roughly 5-6 deg per year. After their appearance, they are present more or less continuously until the following solar minimum. Near solar minimum, the high-latitude coronal activity zones that appeared after the beginning of Cycle 21 monotonically evolved into the MAZ of Cycle 22. It thus appears that we have evidence for parallel overlapping solar cycles that begin every 11 years but last for approximately 19-20 years. Keywords: Solar corona; Solar activity; Solar cycle; Reprints. (jhd) 收起