Description
This paper reports on the spectroscopic investigation of 54 Cepheids, deriving parameters and abundances. These Cepheids extend previous samples by about 35% in number and increase the amount of the Galactic disk coverage, especially in the direction of l~120{deg}. We find that there exists in the Galactic disk at that longitude and at a solar distance of about 3-4kpc a region that has enhanced abundances, <[Fe/H]>~+0.2, with respect to the local region. A simple linear fit to all Cepheid data now extant yields a gradient d[Fe/H]/dR=-0.068+/-0.003dex/kpc. After consideration of the spatial abundance inhomogeneities in the sample, we conclude that the best current estimate of the overall gradient is d[Fe/H]/dR=-0.06dex/kpc.
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