A Study of Convection with δ Scuti Stars in Open Clusters : the Pleiades
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چکیده
In this work we propose a preliminary seismic investigation of δ Scuti stars in the Pleiades cluster, focusing on potential diagnostics of convection and core-overshooting. Taking into account the effect of fast rotation in the modelling, we compare observed frequencies for 4 δ Scuti stars with radial linear instability predictions. A satisfying agreement is reached between the predicted ranges of unstable modes and those derived from observations for " low-mass " stars (∼ 1.55M ⊙). However, a strong disagreement is found for " high-mass " stars (∼ 1.77M ⊙), whatever the mixing length (α) value. These results are compared with previous ones obtained for Praesepe.
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تاریخ انتشار 2002