On the Theoretical Period-Luminosity Relation of Cepheids
نویسنده
چکیده
The theoretical period-luminosity relation for Cepheids was deduced from stellar evolution and pulsation computations. Questions concerning the metallicity dependence of the relation as well as the constancy of the pulsation ‘constant’ Q in the instablility strip were addressed. We found no significant metallicity dependence of either the slope or of the zero-point of the period-luminosity relation. The Q-value, however, varies across the instability strip, in effective temperature as well as in luminosity; its metallicity dependence, on the other hand, is marginal. Subject headings: stars: Cepheids — stars: evolution — stars: pulsation
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