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arXiv · 1111.2096

Statistical Tests for the Metallicity Dependency of the Synthetic Cepheid Period-Luminosity Relations in IRAC Bands

Chow-Choong Ngeow·Marcella Marconi·Ilaria Musella·Michele Cignoni·Shashi Kanbur
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Abstract

The mid-infrared (MIR) period-luminosity (P-L) relations for Cepheids will be important in the JWST era, as it holds the promise of deriving the Hubble constant within 2% accuracy. It is expected that the MIR P-L to be insensitive to metallicity. In this work, we test this assumption of metallicity independent of the IRAC band P-L relation by applying well-known statistical methods to the synthetic P-L slopes from a series of pulsating models with known metallicity. The statistical tests suggest that the P-L slopes in MIR are linearly depending on metallicity.

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Chow-Choong Ngeow, Marcella Marconi, Ilaria Musella, Michele Cignoni, Shashi Kanbur. 2011-11-09. Statistical Tests for the Metallicity Dependency of the Synthetic Cepheid Period-Luminosity Relations in IRAC Bands. https://arxiv.org/abs/1111.2096

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