Stellar evolutionary models for Magellanic Clouds

¹ Osservatorio Astronomico di Roma, via Frascati 33, 00040 Monte Porzio Catone, Italy
² INFN Sezione di Ferrara, via Paradiso 12, 44100 Ferrara, Italy
³ Dipartimento di Fisica, Università di Pisa, via Buonarroti 2, 56127 Pisa, Italy
⁴ INFN Sezione di Pisa, via Buonarroti 2, 56127 Pisa, Italy
⁵ Osservatorio Astronomico di Capodimonte, via Moiariello 16, 80131 Napoli, Italy
⁶ Osservatorio Astronomico di Collurania, via Maggini, 64100 Teramo, Italy
⁷ Dipartimento di Astronomia e Scienza dello Spazio, Largo E. Fermi 5, 50125 Firenze, Italy

Corresponding author: S. Degl'Innocenti, scilla@df.unipi.it

Received: 21 January 2003
Accepted: 6 April 2003

Abstract

We supplement current evolutionary computations concerning Magellanic Cloud stars by exploring the evolutionary behavior of canonical stellar models (i.e., with inefficient core overshooting) with metallicities suitable for stars in the Clouds. After discussing the adequacy of the adopted evolutionary scenario, we present evolutionary sequences as computed following a selected sample of stellar models in the mass range from the Main Sequence till the C ignition or the onset of thermal pulses in the advanced Asymptotic Giant Branch phase. On this basis, cluster isochrones covering the range of ages from ~100 Myr to ~15 Gyr are presented and discussed. To allow a comparison with evolutionary investigations appeared in the recent literature, we computed additional sets of models which take into account moderate core overshooting during the H burning phase, discussing the comparison in terms of current uncertainties in the stellar evolutionary models. Selected predictions constraining the cluster ages are finally discussed, presenting a calibration of the difference in magnitude between the luminous MS termination and the He burning giants in terms of cluster age. Both evolutionary tracks and isochrones have been made available at the node http://gipsy.cjb.net as a first step of a planned “Pisa Evolutionary Library”.