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arXiv · 2411.18854

New pulsating stars detected in EA-type eclipsing binary systems based on TESS data

Xiang-Dong Shi·Sheng-Bang Qian·Lin-Jia Li
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Abstract

Pulsating stars in eclipsing binaries are very important to understand stellar interior structures through astroseismology because their absolute parameters such as the masses and radii can be determined in high precision based on photometric and spectroscopic data. The high-precision and continuously time-series photometric data of the Transiting Exoplanet Survey Satellite (TESS) provides an unprecedented opportunity to search for and study this kind of variable stars in the whole sky. About 1626 Algol type (EA-type) eclipsing binary systems were observed by TESS in the 1-45 sectors with 2-minutes short cadence. By analyzing those TESS data, we found 57 new pulsating stars in EA-type binary stars. The preliminary results show that those binary systems have orbital periods in the range from 0.4 to 27 days, while the periods of pulsating components are in the range from 0.02 to 5 days. It is detected that 43 targets follow the correlation between pulsation and orbital periods of oscillating eclipsing binaries of Algol type (oEA), which may indicate that they are typical oEA stars. The other 14 targets may be other types of variable stars in eclipsing binary systems. These objects are a very interesting source to investigate the binary structures and evolutions as well as to understand the influences of tidal forces and mass transfer on stellar pulsations.

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Xiang-Dong Shi, Sheng-Bang Qian, Lin-Jia Li. 2024-11-28. New pulsating stars detected in EA-type eclipsing binary systems based on TESS data. https://doi.org/10.3847/1538-4365%2Fac59b9

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