Decay rates of sunspot groups from 1874 to 1976

Bibcode
1990Ap&SS.170....3M
DOI
10.1007/BF00652636
Martinez Pillet, V.; Moreno-Insertis, F.; Vazquez, M.
Bibliographical reference

(IAU, European Regional Astronomy Meeting, 11th, La Laguna, Spain, July 3-8, 1989) Astrophysics and Space Science (ISSN 0004-640X), vol. 170, no. 1-2, Aug. 1990, p. 3-7.

Advertised on:
8
1990
Number of authors
3
IAC number of authors
0
Citations
1
Refereed citations
1
Description
The global behavior and fine structure of the distribution of sunspot decay rates from activity cycle 13 to 20 are presented. It is shown that the distribution of this parameter is lognormal. Statistically significantly lower values of decay rates are found in cycles 13, 14, and 18 for isolated spots. The complex groups had no appreciable changes.
Type
Non-refereed
Solar activity
Sunspots
Sunspot cycle

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