The Dependency of the Cepheid Period-Luminosity Relation on Chemical Composition

Autor:	Romaniello, M., Primas, F., Mottini, M., Pedicelli, S., Lemasle, B., Bono, G., Francois, P., Groenewegen, M. A. T., Laney, C. D.
Rok vydání:	2009
Předmět:	Astrophysics - Solar and Stellar Astrophysics Astrophysics - Cosmology and Nongalactic Astrophysics
Druh dokumentu:	Working Paper
DOI:	10.1063/1.3246585
Popis:	The dependency of the Cepheid Period-Luminosity Relation on chemical composition at different wavelengths is assessed via direct detailed abundance analysis of Galactic and Magellanic Cepheids, as derived from high resolution, high signal-to-noise spectra. Our measurements span one order of magnitude in iron content and allow to rule out at the ~ 9 sigma level the universality of the Period-Luminosity Relation in the V band, with metal rich stars being fainter than metal poor ones by ~0.3 mag. The dependency is less pronounced in the K band. Its magnitude and statistical significance decisively depend on detailed distance measurements to individual stars, as inferred via the Infrared Surface Brightness Method. Comment: 3 pages, 2 figures, to be published in "Stellar Pulsation: Challenges for Theory and Observation" (31 May - 5 June, Santa Fe, New Mexico). Minor typos fixed in v2
Databáze:	arXiv
Externí odkaz:	http://arxiv.org/abs/0907.3655 Zobrazit plný text záznamu View this record from Arxiv