Lampens, P. ; Vermeylen, L. ; De Cat, P. ; Sódor, Á. ; Bognár, Zs. ; Frémat, Y. ; Skarka, M. ; Lehmann, H. ; Samadi, A. ; Fox-Machado, L. ; Joshi, S.

Poster presented at "Stars and their variability observed from space - Celebrating the 5th anniversary of BRITE-Constellation", Vienna, Austria on 2019-08-19

Abstract: By means of a study based on multi-epoch, high-resolution spectra of 83 A/F-type candidate hybrid pulsating stars from the Kepler mission collected at various observatories, we derive a (lower) estimate of the fraction of hybrid stars which belong to spectroscopic binary and multiple systems. In the first part (49 hybrid stars), we derived a global multiplicity fraction of 27% at least (Lampens et al. 2018). In the second part, we intend to obtain the same information for another 46 candidate hybrid stars. From a preliminary classification of 43 newly observed targets, we currently find a spectroscopic multiplicity fraction of ∼30%. Spectroscopic observations are on-going. As a plus, we identified systems for which a combined analysis of Time Delays (TDs) with Radial Velocities (RVs) allows to derive accurate orbital elements and mass ratios as well as an identification of the pulsating component. Furthermore, we will analyse the low-frequency regions of the periodograms of these stars based on the exquisite data collected by the Kepler mission.