Pulsation Models for Ultra-low (Z = 0.0004) Metallicity Classical Cepheids

  title={Pulsation Models for Ultra-low (Z = 0.0004) Metallicity Classical Cepheids},
  author={M. Marconi and I. Musella and G. Fiorentino and G. Clementini and A. Aloisi and F. Annibali and R. C. Ramos and A. Saha and M. Tosi and R. Marel},
  journal={The Astrophysical Journal},
Classical Cepheids are primary distance indicators playing a fundamental role in the calibration of the extragalactic distance scale. The possible dependence of their characteristic period-luminosity (PL) relation on chemical composition is still debated in the literature, and the behavior of these pulsators at very low metallicity regimes is almost unexplored. In order to derive constraints on the application of the PL relation at low metal abundances, we investigate the properties of the few… Expand
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  • Physics
  • 2020
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