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arXiv · 1211.4026

On the Metallicity Dependence of Classical Cepheid Light Amplitudes

Daniel J. Majaess·David G. Turner·Wolfgang P. Gieren·Leonid N. Berdnikov·David J. Lane
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Abstract

Classical Cepheids remain a cornerstone of the cosmic distance scale, and thus characterizing the dependence of their light amplitude on metallicity is important. Period-amplitude diagrams constructed for longer-period classical Cepheids in IC 1613, NGC 3109, SMC, NGC 6822, LMC, and the Milky Way imply that very metal-poor Cepheids typically exhibit smaller V-band amplitudes than their metal-rich counterparts. The results provide an alternate interpretation relative to arguments for a null and converse metallicity dependence. The empirical results can be employed to check predictions from theoretical models, to approximate mean abundances for target populations hosting numerous long-period Cepheids, and to facilitate the identification of potentially blended or peculiar objects.

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Daniel J. Majaess, David G. Turner, Wolfgang P. Gieren, Leonid N. Berdnikov, David J. Lane. 2012-11-16. On the Metallicity Dependence of Classical Cepheid Light Amplitudes. https://doi.org/10.1007/s10509-012-1331-z

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