Constraining the third dredge-up via carbon stars in the Magellanic Clouds
Astrophysics
2007-05-23 v1
Abstract
We use the available data for Magellanic Cloud carbon stars to constrain the efficiency of the third dredge-up process in TP-AGB models. We show that star counts in LMC clusters provide quite stringent limits to the lifetime of the C-star phase, with a duration between 2 and 3 Myr for stars in the mass range from 1.5 to 2.8 Msun. Together with the luminosity functions of field C stars, this information allows us to re-calibrate the third dredge-up parameters log T_b_dred and lambda in TP-AGB models that include variable molecular opacities (Marigo 2002). Preliminary results are presented here.
Cite
@article{arxiv.astro-ph/0302020,
title = {Constraining the third dredge-up via carbon stars in the Magellanic Clouds},
author = {L. Girardi and P. Marigo},
journal= {arXiv preprint arXiv:astro-ph/0302020},
year = {2007}
}
Comments
in proceedings of the St. Luc conference ``CNO in the Universe'', eds. C. Charbonnel, D. Schaerer, & G. Meynet, ASP Conference Series, in press