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Chemical abundances of planetary nebulae towards the direction of the galactic anticenter

R. D. D. Costa·M. M. M. Uchida·W. J. Maciel
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Abstract

In this paper we report new observations and derive chemical abundances for a sample of 26 planetary nebulae (PN) located in the anticenter direction. Most of these nebulae are far away objects, located at galactocentric distances greater than about 8 kpc, so that they are particularly useful for the determination of the radial gradients at large distances from the galactic center. A comparison of the present results with previously determined abundances suggests that the radial abundance gradients flatten out at distances larger than about 10 kpc from the center.

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R. D. D. Costa, M. M. M. Uchida, W. J. Maciel. 2004-05-03. Chemical abundances of planetary nebulae towards the direction of the galactic anticenter. https://doi.org/10.1051/0004-6361%3A20034539

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