Description
We have completed spectroscopic studies of 23 Galactic cepheids to determine possible metallicity effects on measuring the zero point of the P-L relation. We find a spread of 0.4dex in [Fe/H], which is not the result of either observational scatter or of a metallicity gradient within the Galactic disk. We find a smaller, less significant spread of 0.2dex in [{alpha}/Fe]. Our results are robust, determined by constancy of [Fe/H] derived at differing temperatures throughout the pulsational cycle, and abundances of two dwarfs compared to U Sgr in the cluster M25. We discuss briefly the effect of metallicity on the P-L relation. We also argue that EV Sct and QZ Nor are overtone pulsators, and that the latter is not a member of the cluster NGC 6067. (Copyright) 1997 American Astronomical Society.
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