First observations of W Virginis stars with K2: detection of period doubling

  title={First observations of W Virginis stars with K2: detection of period doubling},
  author={Emese Plachy and L'aszl'o Moln'ar and M. I. Jurkovic and Radosław Smolec and Paweł Moskalik and Andr'as P'al and L{\'a}szl{\'o} Szabados and R'obert Szab'o},
  journal={Monthly Notices of the Royal Astronomical Society},
We present the first analysis of W Vir stars observed by the Kepler space telescope in the K2 mission. Clear cycle-to-cycle variation were detected in the light curves of KT Sco and the globular cluster member M80-V1. While the variations in the former star seems to be irregular on the short time scale of the K2 data, the latter appears to experience period doubling in its pulsation. Ground-based colour data confirmed that both stars are W Vir-type pulsators, while a comparison with historical… 

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