An estimate of the time variation of the O/H radial gradient from planetary nebulae

Details An estimate of the time variation of the O/H radial gradient from planetary nebulae An estimate of the time variation of the O/H radial gradient from planetary nebulae

2002-10-21

arxiv.org/abs/astro-ph/0210470v1

Astron.Astrophys. 397 (2003) 667-674

Astronomy and Astrophysics

Astrophysics

9 pages, 7 encapsulated postscript figures, LaTeX, uses Astronomy and Astrophysics macro aa.cls, graphicx package, to be publi

Scientific paper

10.1051/0004-6361:20021530

Radial abundance gradients are a common feature of spiral galaxies, and in the case of the Galaxy both the magnitude of the gradients and their variations are among the most important constraints of chemical evolution models. Planetary nebulae (PN) are particularly interesting objects to study the gradients and their variations. Owing to their bright emission spectra, they can be observed even at large galactocentric distances, and the derived abundances are relatively accurate, with uncertainties of about 0.1 to 0.2 dex, particularly for the elements that are not synthesized in their progenitor stars. On the other hand, as the offspring of intermediate mass stars, with main sequence masses in the interval of 1 to 8 solar masses, they are representative of objects with a reasonable age span. In this paper, we present an estimate of the time variation of the O/H radial gradient in a sample containing over 200 nebulae with accurate abundances. Our results are consistent with a flattening of the O/H gradient roughly from -0.11 dex/kpc to -0.06 dex/kpc during the last 9 Gyr, or from -0.08 dex/kpc to -0.06 dex/kpc during the last 5 Gyr.

Affiliated with

Also associated with

No associations

Rating

An estimate of the time variation of the O/H radial gradient from planetary nebulae does not yet have a rating. At this time, there are no reviews or comments for this scientific paper.

If you have personal experience with An estimate of the time variation of the O/H radial gradient from planetary nebulae, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and An estimate of the time variation of the O/H radial gradient from planetary nebulae will most certainly appreciate the feedback.

Rate now

Comments { 0 }

Profile ID: LFWR-SCP-O-355210