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Modeling Kepler Transit Light Curves as False Positives: Rejection of Blend Scenarios for Kepler-9, and Validation of Kepler-9 d, a Super-Earth-Size Planet in a Multiple SystemLight curves from the Kepler Mission contain valuable information on the nature of the phenomena producing the transit-like signals. To assist in exploring the possibility that they are due to an astrophysical false positive we describe a procedure (BLENDER) to model the photometry in terms of a blend rather than a planet orbiting a star. A blend may consist of a background or foreground eclipsing binary (or star-planet pair) whose eclipses are attenuated by the light of the candidate and possibly other stars within the photometric aperture. We apply BLENDER to the case of Kepler-9 (KIC 3323887), a target harboring two previously confirmed Saturn-size planets (Kepler-9 b and Kepler-9 c) showing transit timing variations, and an additional shallower signal with a 1.59 day period suggesting the presence of a super-Earth-size planet. Using BLENDER together with constraints from other follow-up observations we are able to rule out all blends for the two deeper signals and provide independent validation of their planetary nature. For the shallower signal, we rule out a large fraction of the false positives that might mimic the transits. The false alarm rate for remaining blends depends in part (and inversely) on the unknown frequency of small-size planets. Based on several realistic estimates of this frequency, we conclude with very high confidence that this small signal is due to a super-Earth-size planet (Kepler-9 d) in a multiple system, rather than a false positive. The radius is determined to be 1.64(exp)(sub-14),R, and current spectroscopic observations are as yet insufficient to establish its mass.
Document ID
20120009949
Document Type
Reprint (Version printed in journal)
Authors
Torres, Guillermo (Harvard-Smithsonian Center for Astrophysics Cambridge, MA, United States)
Fressin, Francois (Harvard-Smithsonian Center for Astrophysics Cambridge, MA, United States)
Batalha, Natalie M. (San Jose State Univ. San Jose, CA, United States)
Borucki, William J. (NASA Ames Research Center Moffett Field, CA, United States)
Brown, Timothy M. (Las Cumbres Observatory Globabl Telescope Goleta, CA, United States)
Bryson, Stephen T. (NASA Ames Research Center Moffett Field, CA, United States)
Buchhave, Lars A. (Niels Bohr Inst. Copenhagen, Denmark)
Charbonneau, David (Harvard-Smithsonian Center for Astrophysics Cambridge, MA, United States)
Ciardi, David R. (California Inst. of Tech. Pasadena, CA, United States)
Dunham, Edward W. (Lowell Observatory Flagstaff, AZ, United States)
Fabrycky, Daniel C. (Harvard-Smithsonian Center for Astrophysics Cambridge, MA, United States)
Ford, Eric B. (Florida Univ. Gainesville, FL, United States)
Gauthier, Thomas N., III (Jet Propulsion Lab., California Inst. of Tech. Pasadena, CA, United States)
Gilliland, Ronald L. (Space Telescope Science Inst. Baltimore, MD, United States)
Holman, Matthew J. (Harvard-Smithsonian Center for Astrophysics Cambridge, MA, United States)
Howell, Steve B. (National Optical Astronomy Observatories Tucson, AZ, United States)
Isaacson, Howard (San Francisco State Univ. San Francisco, CA, United States)
Jenkins, Jon M. (Search for Extraterrestrial Intelligence Inst. Moffett Field, CA, United States)
Koch, David G. (NASA Ames Research Center Moffett Field, CA, United States)
Latham, David W. (Harvard-Smithsonian Center for Astrophysics Cambridge, MA, United States)
Lissauer, Jack J. (NASA Ames Research Center Moffett Field, CA, United States)
Marcy, Geoffrey W. (California Univ. Berkeley, CA, United States)
Monet, David G. (Naval Observatory Flaggstaff, AZ, United States)
Prsa, Andrej (Villanova Univ. PA, United States)
Quinn, Samuel N. (Harvard-Smithsonian Center for Astrophysics Cambridge, MA, United States)
Date Acquired
August 25, 2013
Publication Date
January 20, 2011
Publication Information
Publication: The Astrophysical Journal
Volume: 727
Issue: 1
Subject Category
Astrophysics
Report/Patent Number
AD-A555746
Distribution Limits
Public
Copyright
Other
Keywords
PLANETARY SYSTEMS
KEPLER TRANSIT
KEPLER-9 D
FALSE POSITIVES