Orbital solutions derived from radial velocities and time delays for four Kepler systems with A/F-type (candidate) hybrid pulsators

0548284 - ASÚ 2022 RIV FR eng J - Journal Article
Lampens, P. - Vermeylen, R. - Frémat, Y. - Sódor, A. - Skarka, Marek - Samadi-Ghadim, A. - Bognár, Zs. - Lehmann, H. - de Cat, P. - Goswami, A. - Dumortier, L.
Orbital solutions derived from radial velocities and time delays for four Kepler systems with A/F-type (candidate) hybrid pulsators.
Astronomy & Astrophysics. Roč. 647, March (2021), č. článku A139. ISSN 0004-6361. E-ISSN 1432-0746
R&D Projects: GA MŠMT(CZ) LTT20015
Institutional support: RVO:67985815
Keywords : spectroscopic * asteroseismology * radial velocities
OECD category: Astronomy (including astrophysics,space science)
Impact factor: 6.240, year: 2021
Method of publishing: Open access with time embargo
https://doi.org/10.1051/0004-6361/202039389

We aim to improve the orbital solutions for those spectroscopic systems with long orbital periods (order of 4-6 years) among the Kepler hybrid stars that we continued to observe.Methods. The orbits are computed based on a simultaneous modelling of the RVs obtained with high-resolution spectrographs and the photometric TDs derived from time-dependent frequency analyses of the Kepler light curves.Results. We refined the orbital solutions of four spectroscopic systems with A/F-type Kepler hybrid component stars: KIC 4480321, 5219533, 8975515, and KIC 9775454. Simultaneous modelling of both data types analysed together enabled us to improve the orbital solutions (all), obtain more robust and accurate information on the mass ratio (some for the first time), and identify the component with the short-period delta Sct-type pulsations (all). The information gained is maximized when one of the components, generally the one exhibiting the delta Sct-type pulsations, is a fast rotator. In several cases, we were also able to derive new constraints for the minimum component masses. From a search for regular frequency patterns in the high-frequency regime of the Fourier transforms of each system, we found no evidence of tidal splitting among the triple systems with close (inner) companions. However, some systems exhibit frequency spacings that can be explained by the mechanism of rotational splitting.
Permanent Link: http://hdl.handle.net/11104/0324384