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Stellar models for very low-mass main-sequence stars: the role of model atmospheres |
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| Authors: | Brocato Cassisi & Castellani |
| Institution: | Osservatorio Astronomico di Collurania, Via M. Maggini, I-64100, Teramo, Italy,;Istituto Nazionale di Fisica Nucleare, LNGS, 67010 Assergi, L'Aquila, Italy,;Universitádegli studi de L'Aquila, Dipartimento di Fisica, Via Vetoio, I-67100, L'Aquila, Italy,;Dipartimento di Fisica, Universitádi Pisa, Piazza Torricelli 2, I-56100, Pisa, Italy |
| Abstract: | We present very low-mass stellar models as computed using non-grey model atmospheres for selected assumptions about the stellar metallicities. The role of atmospheres is discussed and the models are compared with models based on the Eddington approximation, and with similar models that have appeared in the recent literature. Theoretical predictions concerning both the HR diagram location and the mass–luminosity relation are presented and discussed in terms of expectations in selected photometric bands. Comparison with available observational data concerning both galactic globular clusters and dwarfs in the solar neighbourhood reveals a satisfactory agreement together with the existence of some residual mismatches. |
| Keywords: | stars: atmospheres stars: evolution stars: low-mass brown dwarfs stars: Population II globular clusters: general |