Article

Age Distribution of AGB Stars and Central Stars of Planetary Nebulae

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Abstract

We discuss three methods to estimate the age distribution of central stars of planetary nebulae (CSPN) and their progenitor stars. These methods include the use of an age-metallicity relation that also depends on the galactocentric distance, an age-metallicity relation for the Galactic disk, and the determination of ages from the central star masses obtained from the observed nitrogen abundances. We conclude that most CSPN in the Galactic disk have ages under 6 Gyr, and their age distribution is peaked around 2-4 Gyr. These results have been successfully compared with the age distributions of white dwarf stars based on their mass distribution, and on available mass determinations of CSPN.

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