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Using Cepheids to determine the galactic abundance gradient II. Towards the galactic center

S. M. Andrievsky·D. Bersier·V. V. Kovtyukh·R. E. Luck·W. J. Maciel·J. R. D. Lepine·Yu. V. Beletsky
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Abstract

Based on spectra obtained at the Anglo-Australian Observatory, we present a discussion of the metallicity of the galactic disc derived using Cepheids at galactocentric distances 4-6 kpc. Our new results together with previous gradient determination (Paper I) show that the overall abundance distribution within the galactocentric distances 4-11 kpc cannot by represented by a single gradient value. The distribution is more likely bimodal: it is flatter in the solar neighbourhood with a small gradient, and steepens towards the galactic center. The steepening begins at a distance of about 6.6 kpc.

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S. M. Andrievsky, D. Bersier, V. V. Kovtyukh, R. E. Luck, W. J. Maciel, J. R. D. Lepine, Yu. V. Beletsky. 2001-12-21. Using Cepheids to determine the galactic abundance gradient II. Towards the galactic center. https://doi.org/10.1051/0004-6361%3A20020016

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