KIC 3240411 – the hottest known SPB star with the asymptotic g–mode period spacing

Abstract

We report the discovery of the hottest hybrid B--type pulsator, KIC\,3240411, that exhibits the period spacing in the low--frequency range. This pattern is associated with asymptotic properties of high-order gravity (g) modes. Our seismic modelling made simultaneously with the mode identification shows that dipole axisymmetric modes best fit the observations. Evolutionary models are computed with MESA code and pulsational models with the linear non-adiabatic code employing the traditional approximation to include the effects of rotation. The problem of mode excitation is discussed. We confirm that significant modification is indispensable to explain an instability of both pressure and gravity modes in the observed frequency ranges of KIC\,3240411.