Synthetic Cepheid Period–Luminosity and Period–Color Relations in Spitzer’s IRAC Bands
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.
KeywordsLight Curf Hubble Constant Large Magellanic Cloud Instability Strip Stellar Pulsation
CCN thanks the funding from National Science Council (of Taiwan) under the contract NSC 98-2112-M-008-013-MY3.