When a Period Is Not a Full Stop: Light Curve Structure Reveals Fundamental Parameters of Cepheid and RR Lyrae Stars

  title={When a Period Is Not a Full Stop: Light Curve Structure Reveals Fundamental Parameters of Cepheid and RR Lyrae Stars},
  author={Earl Patrick Bellinger and Shashi Kanbur and Anupam Bhardwaj and Marcella Marconi},
The period of pulsation and the structure of the light curve for Cepheid and RR Lyrae variables depend on the fundamental parameters of the star: mass, radius, luminosity, and effective temperature. Here, we train artificial neural networks on theoretical pulsation models to predict the fundamental parameters of these stars based on their period and light-curve structure. We find significant improvements to estimates of these parameters made using light-curve structure and period over… 

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