Evidence of chaotic modes in the analysis of four δ Scuti stars

Barceló-Forteza, S.; Roca-Cortés, T.; García Hernández, A.; García, R. A.
Bibliographical reference

Astronomy and Astrophysics, Volume 601, id.A57, 14 pp.

Advertised on:
5
2017
Number of authors
4
IAC number of authors
2
Citations
16
Refereed citations
14
Description
Context. Since CoRoT observations unveiled the very low amplitude modes that form a flat plateau in the power spectrum structure of δ Scuti stars, the nature of this phenomenon, including the possibility of spurious signals due to the light curve analysis, has been a matter of long-standing scientific debate. Aims: We contribute to this debate by finding the structural parameters of a sample of four δ Scuti stars, CID 546, CID 3619, CID 8669, and KIC 5892969, and looking for a possible relation between these stars' structural parameters and their power spectrum structure. Methods: For the purposes of characterization, we developed a method of studying and analysing the power spectrum with high precision and have applied it to both CoRoT and Kepler light curves. Results: We obtain the best estimates to date of these stars' structural parameters. Moreover, we observe that the power spectrum structure depends on the inclination, oblateness, and convective efficiency of each star. Conclusions: Our results suggest that the power spectrum structure is real and is possibly formed by 2-period island modes and chaotic modes.
Related projects
Helio and Asteroseismology
Helio and Astero-Seismology and Exoplanets Search
The principal objectives of this project are: 1) to study the structure and dynamics of the solar interior, 2) to extend this study to other stars, 3) to search for extrasolar planets using photometric methods (primarily by transits of their host stars) and their characterization (using radial velocity information) and 4) the study of the planetary
Savita
Mathur