IALP   13078
INSTITUTO DE ASTROFISICA LA PLATA
Unidad Ejecutora - UE
artículos
Título:
Asteroseismic inferences on GW Virginis variable stars in the frame of new PG 1159 evolutionary models
Autor/es:
CORSICO, A. H.; ALTHAUS, L. G.
Revista:
ASTRONOMY AND ASTROPHYSICS
Editorial:
EDP Sciences
Referencias:
Año: 2006 vol. 454 p. 863 - 881
ISSN:
0004-6361
Resumen:
An adiabatic, nonradial pulsation study of GW Vir starsis presented. The pulsation calculations are based on PG1159 evolutionary sequences with different stellar masses artificially derived from a full evolutionary sequence of 0.5895 Msun that has been computed taking into account the evolutionary history of the progenitor star. The artificial sequences were constructed by appropriately scaling the stellar mass of the 0.5895 Msun sequence well before the models reach the low-luminosity, high-gravity stage of the GW Vir domain. We compute g-mode pulsation periods appropriate to GW Vir variable stars. The implications for the mode-trapping properties of our PG 1159 models are discussed at length. We found that the mode-trapping features characterizing our PG 1159 models are mostly fixed by the stepped shape of the core chemical profile left by prior convective overshooting. This is particularly true at least for the range of periods observed in GW Vir stars. In addition, we make asteroseismic inferences about the internal structure of the GW Vir stars PG 1159-035, PG 2131+066, PG 1707+427 and PG 0122+200.