Evidence for compact binary systems around Kepler red giants

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Colman , Isabel , ; Huber , Daniel ; Bedding , Timothy , ; Kuszlewicz , James , ; Yu , Jie , ; Beck , Paul , ; Elsworth , Yvonne , ; García , Rafael , ; Kawaler , Steven , ; Mathur , Savita , ; Stello , Dennis , ; White , Timothy , (2017)
  • Publisher: HAL CCSD
  • Related identifiers: doi: 10.1093/mnras/stx1056
  • Subject: Astrophysics - Solar and Stellar Astrophysics | stars: oscillations (including pulsations) | (stars:) binaries (including multiple): close | [ SDU ] Sciences of the Universe [physics]
    arxiv: Astrophysics::Galaxy Astrophysics | Astrophysics::Cosmology and Extragalactic Astrophysics | Astrophysics::Earth and Planetary Astrophysics | Astrophysics::Solar and Stellar Astrophysics

We present an analysis of 168 oscillating red giants from NASA's $Kepler$ mission that exhibit anomalous peaks in their Fourier amplitude spectra. These peaks result from ellipsoidal variations which are indicative of binary star systems, at frequencies such that the orbit of any stellar companion would be within the convective envelope of the red giant. Alternatively, the observed phenomenon may be due to a close binary orbiting a red giant in a triple system, or chance alignments of foreground or background binary systems contaminating the target pixel aperture. We identify 87 stars in the sample as chance alignments using a combination of pixel Fourier analysis and difference imaging. We find that in the remaining 81 cases the anomalous peaks are indistinguishable from the target star to within 4$''$, suggesting a physical association. We examine a Galaxia model of the $Kepler$ field of view to estimate background star counts and find that it is highly unlikely that all targets can be explained by chance alignments. From this, we conclude that these stars may comprise a population of physically associated systems.
  • References (23)
    23 references, page 1 of 3

    Baranec C. et al., 2011, in Adaptive Optics: Methods, Analysis and Applications (AO), AWA2, 3 pages Beck P. G. et al., 2014, Astronomy and Astrophysics, 564, A36

    Beck P. G. et al., 2012, Nature, 481, 55 Bedding T. R. et al., 2010, The Astrophysical Journal Letters, 713, L176

    Bedding T. R. et al., 2011, Nature, 471, 608 Borucki W. J. et al., 2010, Science, 327, 977 Bryson S. T. et al., 2013, Publications of the Astronomical Society of the Pacific, 125, 889

    Casagrande L. et al., 2016, Monthly Notices of the Royal Astronomical Society, 455, 987

    Casali M. et al., 2007, Astronomy and Astrophysics, 467, 777

    Derekas A. et al., 2011, Science, 332, 216 Fuller J., Derekas A., Borkovits T., Huber D., Bedding T. R., Kiss L. L., 2013, Monthly Notices of the Royal Astronomical Society, 429, 2425

    Garc´ıa R. A. et al., 2011, Monthly Notices of the Royal Astronomical Society, 414, L6

    Gaulme P., Jackiewicz J., Appourchaux T., Mosser B., 2014, The Astrophysical Journal, 785, 5 Hambly N. C. et al., 2008, Monthly Notices of the Royal Astronomical Society, 384, 637

    Hekker S., Christensen-Dalsgaard J., 2016, ArXiv e-prints, 1609, arXiv:1609.07487

    Hewett P. C., Warren S. J., Leggett S. K., Hodgkin S. T., 2006, Monthly Notices of the Royal Astronomical Society, 367, 454

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