BEER Analysis of Kepler and CoRoT Light Curves. IV. Discovery of Four New Low-mass White-Dwarf Companions in the Kepler Data
| Autor: | David W. Latham, Simchon Faigler, Flavien Kiefer, Steven Bloemen, Tsevi Mazeh, Ilya Kull |
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| Rok vydání: | 2015 |
| Předmět: |
Earth and Planetary Astrophysics (astro-ph.EP)
Physics education.field_of_study media_common.quotation_subject Astronomy Population FOS: Physical sciences White dwarf Astronomy and Astrophysics Astrophysics Light curve Kepler Astrophysics - Solar and Stellar Astrophysics Space and Planetary Science Primary (astronomy) ComputingMethodologies_DOCUMENTANDTEXTPROCESSING Eccentricity (behavior) education Low Mass Solar and Stellar Astrophysics (astro-ph.SR) media_common Eclipse Astrophysics - Earth and Planetary Astrophysics |
| Zdroj: | The Astrophysical Journal, 815, 1, pp. 26 The Astrophysical Journal, 815, 26 |
| ISSN: | 0004-637X |
| Popis: | We report the discovery of four short-period eclipsing systems in the Kepler light curves, consisting of an A-star primary and a low-mass white dwarf (WD) secondary (dA+WD) - KIC 4169521, KOI-3818, KIC 2851474, and KIC 9285587. The systems show BEaming, Ellipsoidal and Reflection (BEER) phase modulations together with primary and secondary eclipses. These add to the 6 Kepler and 18 WASP short-period eclipsing dA+WD binaries that were previously known. The light curves, together with follow-up spectroscopic observations, allow us to derive the masses, radii, and effective temperatures of the two components of the four systems. The orbital periods, of 1.17-3.82 days, and WD masses, of 0.19-0.22 Msun, are similar to those of the previously known systems. The WD radii of KOI-3818, KIC 2851474, and KIC 9285587 are 0.026, 0.035, and 0.026 Rsun, respectively, the smallest WD radii derived so far for short-period eclipsing dA+WD binaries. These three binaries extend the previously known population to older systems with cooler and smaller WD secondaries. KOI-3818 displays evidence for a fast-rotating primary and a minute but significant eccentricity of ~0.0015. These features are probably the outcome of the mass-transfer process. 23 pages, 7 figures and 4 tables. Accepted by The Astrophysical Journal |
| Databáze: | OpenAIRE |
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