The Cepheid Instability Strip in the GAIA Era

Giuseppe Bono

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The Cepheid Instability Strip in the GAIA Era

Giuseppe Bono

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Abstract

We present recent results concerning distance determinations based on the two most popular primary distance indicators, namely classical Cepheids and RR Lyrae. We discuss the problems affecting the Cepheid distance scale, and in particular the dependence of fundamental Period-Luminosity (PL) and Period-Luminosity-Color (PLC) relations on the metal content. The key advantages in using the K-band PL relation of RR Lyrae stars when compared with the M_V vs [Fe/H] are also presented.

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Giuseppe Bono. 2003-03-21. The Cepheid Instability Strip in the GAIA Era. https://arxiv.org/abs/astro-ph/0303490

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