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Problems with exoplanets around sdBV and sdO stars from primary Kepler field

Published online by Cambridge University Press:  13 January 2020

Jerzy Krzesinski
Affiliation:
Mt. Suhora Observatory, Pedagogical University of Cracow, ul. Podchora̡żych 2, 30-084 Cracow, Poland email: jk@oa.uj.edu.pl Astronomical Observatory, Jagiellonian University, ul. Orla 171, PL-30-244 Cracow, Poland
A. Blokesz
Affiliation:
Mt. Suhora Observatory, Pedagogical University of Cracow, ul. Podchora̡żych 2, 30-084 Cracow, Poland email: jk@oa.uj.edu.pl
W. Ogłoza
Affiliation:
Mt. Suhora Observatory, Pedagogical University of Cracow, ul. Podchora̡żych 2, 30-084 Cracow, Poland email: jk@oa.uj.edu.pl
M. Dróżdż
Affiliation:
Mt. Suhora Observatory, Pedagogical University of Cracow, ul. Podchora̡żych 2, 30-084 Cracow, Poland email: jk@oa.uj.edu.pl
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Abstract

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The existence of exoplanets around evolved objects is one of the most interesting subjects from the viewpoint of planetary system evolution and its fate. What happens to the exoplanets engulfed in the host star envelope during red giant branch (RGB) phase? Can planets survive this evolutionary stage of the host star? Here, we are showing that at least some of the exoplanetary candidates recently found around a couple of sdBV stars, KIC 5807616 and KIC 10001893, might not be exoplanets after all. One “exoplanetary signal” visible in the light curve FT of KIC 10001893 can be just a frequency combination of stellar pulsation modes, while others are likely artifacts. Similarly, low frequency signals found in KIC 5807616 light curve FT, are beating frequencies of stellar oscillations, rather than resulting from the exoplanetary radiation. We also analyzed frequency and amplitude changes of the signal around 0.256 c/d (∼3.9 day) visible in the light curve FT of the KIC 10449976 sdO star. Our simulations show that it is difficult to reproduce the observed signal frequency variations by the weather changes in the exoplanet atmosphere.

Type
Contributed Papers
Copyright
© International Astronomical Union 2020 

References

Bear, E., & Soker, N. 2014, MNRAS, 437, 1400 CrossRefGoogle Scholar
Charpinet, S., Fontaine, G., Brassard, P., et al. 2011, Nature, 480, 496 10.1038/nature10631CrossRefGoogle Scholar
Hansen, C. J., Winget, D. E., & Kawaler, S. D. 1985, ApJ, 297, 544 CrossRefGoogle Scholar
Jeffery, C. S., Ramsay, G., Naslim, N., et al. 2013, MNRAS, 429, 3207 10.1093/mnras/sts579CrossRefGoogle Scholar
Krzesinski, J. 2015, A&A, 581, A7 Google Scholar
Silvotti, R., Charpinet, S., Green, E., et al. 2014, A&A, 570, A130 Google Scholar
Uzundag, M., Baran, A. S., Østensen, R. H., et al. 2017, MNRAS, 472, 700 10.1093/mnras/stx2011CrossRefGoogle Scholar