W. J. Maciel - Abstract #137


RADIAL ABUNDANCE GRADIENTS FROM PLANETARY NEBULAE AND YOUNG OBJECTS: AGE EFFECTS

W. J. Maciel, T. S. Rodrigues, R. D. D. Costa

IAU Symposium No. 283, Ed. A. Manchado, L. Stanghellini, D. Schönberner, 424-425 (2012)

We discuss the effects on the time variation of the gradients resulting from our determinations of the age distributions of CSPN. The main conclusions are: (i) for most CSPN with accurate radial velocities the kinematic ages are usually under 3 Gyr, so that the differences between the gradients of these objects and of younger objects are expected to be small; (ii) results based on age-metallicity relations suggest that there is an older PN population for which the gradients are steeper, in agreement with open cluster data.

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