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A comparison of the time variation of radial abundance gradients from planetary nebulae and open clusters

W. J. Maciel·R. D. D. Costa·P. A. L. Ferreira
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Abstract

The temporal behaviour of the radial abundance gradients has important consequences on models for the chemical evolution of the Galaxy. We present a comparison of the time variation of the abundance gradients in the Milky Way disk as determined from a sample of planetary nebulae and open clusters. We conclude that the [Fe/H] gradients as measured in open cluster stars strongly support the time flattening of the abundance gradient as recently determined from O/H measurements in planetary nebulae. We estimate the average flattening rate in the time interval 10 Myr < t < 5 Gyr as roughly 0.005 dex kpc-1 Gyr-1.

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W. J. Maciel, R. D. D. Costa, P. A. L. Ferreira. 2004-01-07. A comparison of the time variation of radial abundance gradients from planetary nebulae and open clusters. https://arxiv.org/abs/astro-ph/0401076

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