### Quasi-periodicities of Sunspot Area
Fluctuations

**Ryszarda Getko**

Astronomical Institute, University of Wroclaw

The sunspot area fluctuations over the epoch of 12 solar
cycles (12-23) are investigated. I apply auto-correlation and wavelet analyses
to the sunspot area fluctuations and their transformations with a constant
variance for the northern and the southern hemispheres of the Sun. Because of
the asymmetry of the fluctuation probability distribution, the positive and the
negative fluctuations are considered separately. For positive fluctuations the
auto-correlation analysis shows three statistically significant
quasi-periodicities at about 10, 17 and 23 solar rotations. For more than 50% of
solar cycles in each hemisphere two last quasi-periods (17 and 23 rotations) can
be represented as the multiple of the shortest quasi-period (from the interval
[7, 13] rotations). The wavelet analysis gives the same results as the
auto-correlation analysis for the shortest quasi-period. For the fluctuation
time series the correlation coefficient between these ewavelet and the
auto-correlation results is about 0.9 for 87% of the auto-correlation peaks. For
the positive fluctuation time series it is also 0.9 for 72% of the
auto-correlation peaks.