New Insights into Pulsating Stars in Eclipsing Binary Systems

A recent study titled "Eclipse mapping study of the eclipsing binary KIC~3858884 with hybrid δ~Sct/γ~Dor component" by A. Bókon, I. B. Bíró, and A. Derekas explores the pulsating stars in the eclipsing binary system KIC~3858884. The research focuses on identifying the dominant pulsation modes using photometric methods, leveraging data from the Kepler space telescope.

The study successfully separated the signals from the eclipsing binary and the pulsations, allowing for refined binary model and pulsation parameters. Notably, the researchers utilized Échelle diagram diagnostics to pinpoint the frequencies most affected by the eclipses. They also applied direct fitting methods that assumed spherical harmonic surface patterns to determine the orientation of the symmetry axis and infer surface mode numbers.

Among the findings, the researchers identified seven peaks, including two dominant modes that exhibited modulations during secondary eclipses. For the first time, they detected two hidden modes that intensified during eclipses, with only one frequency traced back to the primary star. The study reconstructed surface patterns and determined mode numbers for most selected frequencies, revealing one radial and three sectoral modes, including the hidden modes identified as (3,±1) and (2,±1). The results indicate a partial disagreement between the methods used, suggesting that the strongest modes may deviate from strict spherical harmonics.

This research contributes to the understanding of pulsating stars within binary systems and may have implications for future studies in stellar astrophysics. The full paper can be accessed on arXiv under the identifier arXiv:2408.14464.