Constraining the third dredge-up via carbon stars in the Magellanic Clouds

L. Girardi; P. Marigo

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arXiv · astro-ph/0302020

Constraining the third dredge-up via carbon stars in the Magellanic Clouds

L. Girardi·P. Marigo

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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.

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L. Girardi, P. Marigo. 2003-02-03. Constraining the third dredge-up via carbon stars in the Magellanic Clouds. https://arxiv.org/abs/astro-ph/0302020

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