CHEMICAL ABUNDANCES OF GALACTIC CEPHEID VARIABLES THAT CALIBRATE THE P-L RELATION

We have completed spectroscopic studies of 23 Galactic cepheids to det ermine possible metallicity effects on measuring the zero point of the P-L relation. We find a spread of 0.4 dex in [Fe/H], which is not the result of either observational scatter or of a metallicity gradient w ithin the Galactic disk. We find a smaller, less significant spread of 0.2 dex in II [alpha/Fe]. Our results are robust, determined by const ancy of [Fe/H] derived at differing temperatures throughout the pulsat ional cycle, and abundances of two dwarfs compared to U Sgr in the clu ster M25. We discuss briefly the effect of metallicity on the P-L rela tion. We also EV Set and QZ Nor are overtone pulsators, and that the l atter is not a member of the cluster NGC 6067. (C) 1997 American Astro nomical Society.