The Five Planets in the Kepler296 Binary System All Orbit the Primary: A Statistical and Analytical Analysis
Abstract
Kepler296 is a binary star system with two Mdwarf components separated by 0.″2. Five transiting planets have been confirmed to be associated with the Kepler296 system; given the evidence to date, however, the planets could in principle orbit either star. This ambiguity has made it difficult to constrain both the orbital and physical properties of the planets. Using both statistical and analytical arguments, this paper shows that all five planets are highly likely to orbit the primary star in this system. We performed a MarkovChain Monte Carlo simulation using a five transiting planet model, leaving the stellar density and dilution with uniform priors. Using importance sampling, we compared the model probabilities under the priors of the planets orbiting either the brighter or the fainter component of the binary. A model where the planets orbit the brighter component, Kepler296A, is strongly preferred by the data. Combined with our assertion that all five planets orbit the same star, the two outer planets in the system, Kepler296 Ae and Kepler296 Af, have radii of 1.53 ± 0.26 and 1.80 ± 0.31 {R}_{\oplus }, respectively, and receive incident stellar fluxes of 1.40 ± 0.23 and 0.62 ± 0.10 times the incident flux the Earth receives from the Sun. This level of irradiation places both planets within or close to the circumstellar habitable zone of their parent star.
 Publication:

The Astrophysical Journal
 Pub Date:
 August 2015
 DOI:
 10.1088/0004637X/809/1/7
 arXiv:
 arXiv:1505.01845
 Bibcode:
 2015ApJ...809....7B
 Keywords:

 binaries: general;
 methods: data analysis;
 methods: statistical;
 planetary systems;
 stars: individual: Kepler296;
 KIC 11497958;
 KOI1422;
 techniques: photometric;
 Astrophysics  Earth and Planetary Astrophysics
 EPrint:
 Accepted for publication in ApJ