Asteroseismology of Delta Scuti Stars – A Parameter Study

Abstract

AbstractWe assess the potential of asteroseismology for determining the fundamental properties of individual δ Scuti stars. We computed a grid of evolution and adiabatic pulsation models to study systematic changes in l = 0,1,2, and 3 modes as functions of fundamental stellar properties. Mass has the strongest effect on evolution and on pulsation, followed by the metal abundance. Changes to the helium content have very little effect on the frequencies until near the end of the main sequence. Changes to each of the four parameters change the p-mode frequencies more than they do the g- and mixed-mode frequencies, suggesting that these parameters have a greater effect on the outer layers of the star. We also present pulsation models of FG Virginis, outlining a possible method of locating favorable models in the stellar parameter space based upon a definitive identification of only two modes. We plot evolution models on the (period-period ratio) and (temperature-period ratio) planes to select candidate models, and modify the core overshooting parameter to fit the observed star.