Atmospheric parameters and pulsational properties for a sample of δSct, γDor, and hybrid Kepler targets

الأصل · EN

We report spectroscopic observations for 19 δSct candidates observed by the Kepler satellite both in long and short cadence mode. For all these stars, by using spectral synthesis, we derive the effective temperature, the surface gravity and the projected rotational velocity. An equivalent spectral type classification has been also performed for all stars in the sample. These determinations are fundamental for modelling the frequency spectra that will be extracted from the Kepler data for asteroseismic inference. For all the 19 stars, we present also periodograms obtained from Kepler data. We find that all stars show peaks in both low- (γDor; g mode) and high-frequency (δSct; p mode) regions. Using the amplitudes and considering 5c/d as a boundary frequency, we classified 3 stars as pure γDor, 4 as γDor-δhybrid, Sct, 5 as δSct-γDor hybrid, and 6 as pure δSct. The only exception is the star KIC05296877 which we suggest could be a binary.