TIME-FREQUENCY ANALYSIS OF 3 STRONGLY VARIABLE WOLF-RAYET STARS - WR-6, WR-134, AND WR-123

We apply the technique of time-frequency analysis to look for temporal changes in the variability power spectrum of the three strongly varia ble Wolf-Rayet stars, WR 6, WR 134, and WR 123, for which relatively l ong strings of homogeneous photometry are available. The observed chan ges of the power spectra may be related to the gradual restructuring o f the stellar wind in the presence of ''active'' regions and/or nonrad ial pulsations or, in the case of the long-term variability of WR 134, caused by the presence of a low-mass companion.