Some Features of the Two Sunspot Group Populations’ Properties
This paper describes some features of the two sunspot group populations’ properties: Large Long-living Groups, LLG, and Small Short-living, SSG (each distributed lognormally), divided by the lifetime of the group (less and strictly more than 5 days). It is shown that the relative fraction of LLG varies with the latitude from 0.45 at mid-latitudes to 0.25–0.30 at low and high latitudes. The SSG has a wider spread in latitude than the LLG. It is shown that the N-S asymmetry is an overall global process to which both the LLG and the SSG are exposed. At the same time, the asymmetry of LLG shows a slightly higher dispersion of oscillations than the asymmetry of SSG. Other properties of sunspot groups in the context of the two separate populations existence are considered.
This work was supported in part by the Russian Foundation for Basic Research (grants 16-02-00090, 18-32-00555, 16-02-00749 ) and the program of the Presidium of the Russian Academy of Sciences no. 28.
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