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arXiv · 1111.2100

Synthetic Cepheid Period-Luminosity & Period-Color Relations in Spitzer's IRAC Bands

C. -C. Ngeow·M. Marconi·I. Musella·M. Cignoni·M. Marengo·S. Kanbur
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Abstract

The mid-infrared period-luminosity (P-L) relation for Cepheids will be important in the JWST era, as it holds the promise of deriving the Hubble constant within 2% accuracy. We present the synthetic P-L and period-color (P-C) relations, derived from a series of stellar pulsation models with varying helium and metallicity abundance, in the Spitzer IRAC bands. Selected synthetic P-L and P-C relations were compared to the empirical relations derived from Galactic and Large Magellanic Cloud Cepheids. We also present the empirical P-L relations based on the latest distance measurements using infrared surface brightness techniques.

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C. -C. Ngeow, M. Marconi, I. Musella, M. Cignoni, M. Marengo, S. Kanbur. 2011-11-09. Synthetic Cepheid Period-Luminosity & Period-Color Relations in Spitzer's IRAC Bands. https://arxiv.org/abs/1111.2100

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