Long-Term Light Curves of Cepheid Variables (Abstract)

Volume 34 number 2 (2006)

Grant Foster

Abstract

(Abstract only) We have analyzed the light curves of sixty-five Cepheid variables, using visual data from the American Association of Variable Star Observers (AAVSO). We find that Cepheid pulsations are not nearly so constant as is often believed; half of our well-observed sample show episodes of period change, in addition to long-term period evolution. We derive the Fourier decomposition coefficients for the sample, and present mean light curves for the best-observed stars. We also find that the light curve shape is usually well approximated by a “bent sawtooth” wave, which can account for the coefficients of the Fourier series.