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arXiv · 2504.12940

A study of Andromeda to improve our knowledge on the evolution and dust production by AGB stars

Claudio Gavetti·Paolo Ventura·Flavia Dell'Agli·Fabio La Franca·Ester Marini·Matteo Correnti·Marco Tailo
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Abstract

We study the AGB population of the galaxy M31, based on available HST and Spitzer data, to characterize the individual sources in terms of mass, metallicity and formation epoch of the progenitors. Particular attention is dedicated to the derivation of the dust production rate of the stars, in the attempt of determining the global current dust production rate of the galaxy, divided between the silicates and the carbonaceous dust contributions. We use results from stellar evolution modelling complemented by the description of the dust formation process in the wind, to be used in a population synthesis approach, based on the star formation history and age-metallicity relationship obtained in previous investigations. The comparison between the results from synthetic modelling and the data available are used for the characterization of AGB stars in M31. We find that the bulk of the AGB population of M31 is composed by low-mass stars of different metallicity formed between 6 Gyr and 14 Gyr ago, with an additional, significant contribution from the progeny of 1.7-2.5Msun stars formed during the secondary peak in the star formation, which occurred between 1 and 2 Gyr ago. The dust production rate of the galaxy is mostly provided by carbon stars, whose contribution is of the order of 4x10^{-4} Msun/yr, completed by silicates production from massive AGB stars, occurring at a rate of 6x10^{-5} Msun/yr. The implications of the present results on the reliability of AGB modelling are also commented.

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Claudio Gavetti, Paolo Ventura, Flavia Dell'Agli, Fabio La Franca, Ester Marini, Matteo Correnti, Marco Tailo. 2025-04-17. A study of Andromeda to improve our knowledge on the evolution and dust production by AGB stars. https://arxiv.org/abs/2504.12940

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