The secret lives of Cepheids: evolutionary changes and pulsation-induced shock heating in the prototype classical Cepheid δ Cep

@article{Engle2014TheSL,
  title={The secret lives of Cepheids: evolutionary changes and pulsation-induced shock heating in the prototype classical Cepheid $\delta$ Cep},
  author={Scott G. Engle and Edward F. Guinan and Graham M. Harper and Hilding R. Neilson and Nancy Remage Evans},
  journal={The Astrophysical Journal},
  year={2014},
  volume={794},
  pages={80}
}
Over the past decade, the Secret Lives of Cepheids (SLiC) program has been carried out at Villanova University to study aspects and behaviors of classical Cepheids that are still not well understood. In this, the first of several planned papers on program Cepheids, we report the current results for δ Cep, the Cepheid prototype. Ongoing photometry has been obtained to search for changes in the pulsation period, light-curve morphology, and amplitude. Combining our photometry with the times of… 

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