Time-Frequency Analysis of Three Strongly Variable Wolf-Rayet Stars: WR 6, WR 134, and WR 123

Open Access

1 June 1998

journal article
research article
Published by American Astronomical Society in The Astrophysical Journal

Vol. 499 (2) , L195-L198
https://doi.org/10.1086/311358

Abstract

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

Keywords

This publication has 22 references indexed in Scilit:

Wavelet Analysis of Stellar Chromospheric Activity Variations
The Astrophysical Journal, 1997
Understanding Libration Via Time-Frequency Analysis
The Astronomical Journal, 1997
Time-Frequency Analysis and Pulsation Modes of LPV Stars.I. omicron Ceti
The Astronomical Journal, 1997
Tools for the Analysis of Chaotic Data
Annals of the New York Academy of Sciences, 1997
Preface
Annals of the New York Academy of Sciences, 1997
Wavelets for period analysis of unevenly sampled time series
The Astronomical Journal, 1996
Multi-colour photometric and spectroscopic monitoring of the WN5 star EZ Canis Majoris
Astronomy and Astrophysics Supplement Series, 1996
Signal analysis by means of time-frequency (Wigner-type) distributions-applications to sonar and radar echoes
Proceedings of the IEEE, 1996
The application of two-dimensional signal transformations to the analysis and synthesis of structural excitations observed in acoustical scattering
Proceedings of the IEEE, 1996
A unique period for the WN5 star EZ CMa
The Astronomical Journal, 1994