TRANSIT TIMING OBSERVATIONS FROM KEPLER. II. CONFIRMATION OF TWO MULTIPLANET SYSTEMS VIA A NON-PARAMETRIC CORRELATION ANALYSIS

We present a new method for confirming transiting planets based on the combination of transit timing variations (TTVs) and dynamical stability. Correlated TTVs provide evidence that the pair of bodies is in the same physical system. Orbital stability provides upper limits for the masses of the transiting companions that are in the planetary regime. This paper describes a non-parametric technique for quantifying the statistical significance of TTVs based on the correlation of two TTV data sets. We apply this method to an analysis of the TTVs of two stars with multiple transiting planet candidates identified by Kepler. We confirm four transiting planets in two multiple-planet systems based on their TTVs and the constraints imposed by dynamical stability. An additional three candidates in these same systems are not confirmed as planets, but are likely to be validated as real planets once further observations and analyses are possible. If all were confirmed, these systems would be near 4:6:9 and 2:4:6:9 period commensurabilities. Our results demonstrate that TTVs provide a powerful tool for confirming transiting planets, including low-mass planets and planets around faint stars for which Doppler follow-up is not practical with existing facilities. Continued Kepler observations will dramatically improve the constraints on the planet masses and orbits and provide sensitivity for detecting additional non-transiting planets. If Kepler observations were extended to eight years, then a similar analysis could likely confirm systems with multiple closely spaced, small transiting planets in or near the habitable zone of solar-type stars.

Howard Isaacson | Debra A. Fischer | Phillip J. MacQueen | NOAO | David Charbonneau | William F. Welsh | SETI Institute | Peter Tenenbaum | Jon M. Jenkins | Santa Barbara | Stephen T. Bryson | Joseph D. Twicken | Avi Shporer | Jason H. Steffen | Eric B. Ford | University of California | William J. Borucki | David G. Koch | Natalie M. Batalha | Douglas A. Caldwell | Berkeley | Michael R. Haas | Jack J. Lissauer | Bruce D. Clarke | Susan E. Thompson | Steve B. Howell | Francois Fressin | Mark E. Everett | Darin Ragozzine | Sean McCauliff | Christopher Allen | Jason F. Rowe | Samuel N. Quinn | Guillermo Torres | Daniel C. Fabrycky | Martin Still | William D. Cochran | Robert C. Morehead | University of Hertfordshire | Yale University | David W. Latham | Las Cumbres Observatory Global Telescope | Harvard-Smithsonian Center for Astrophysics | Geoffrey W. Marcy | Althea V. Moorhead | Christopher J. Burke | StSci | Matthew J. Holman | San Diego State University | Elisa Quintana | NASA Ames | Elliott Horch | Khadeejah A. Ibrahim | Lars A. Buchhave | U. California | Hubble Fellow | F. Fressin | E. Ford | F. Mullally | Avi Shporer | M. Holman | Stsci | J. Lissauer | R. Gilliland | M. Everett | N. Ames | U. Hertfordshire | P. Tenenbaum | L. Buchhave | D. Latham | S. Thompson | D. Charbonneau | G. Marcy | H. Isaacson | J. Rowe | J. Jenkins | S. Bryson | S. Howell | T. Gautier | N. Batalha | D. Fischer | S. Quinn | W. Borucki | D. Koch | D. Caldwell | C. Burke | W. Cochran | M. Endl | P. MacQueen | G. Torres | J. Steffen | D. Fabrycky | P. Lucas | W. Welsh | E. Quintana | M. Still | J. Twicken | J. D'esert | J. Carter | Jie Li | S. McCauliff | B. Clarke | R. C. Morehead | D. Ragozzine | S. Institute | F. C. F. P. Astrophysics | K. Ibrahim | Bay Area Environmental Research InstituteNASA Ames Res Center | Niels Bohr Institute | Natural History Museum of Denmark | M. Observatory | Orbital Sciences CorporationNASA Ames Research Center | E. Horch | A. Moorhead | C. Allen | Noao | UCOLick Observatory | Santa Barbara | Jean-Michel D'esert | Michael Endl | JPLCaltech | Thomas N. Gautier | Joshua A. Carter | UCOLick Observatory | Hubble Fellow | Ron L. Gilliland | Jie Li | Philip Lucas | Fergal R. Mullally | San Jose State University | P. Macqueen | Bill Wohler University of Florida | Fermilab Center for Particle Astrophysics | McDonald Observatory | Southern Connecticut State University | M. Haas | H. C. F. Astrophysics | Yale University | B. A. E. R. I. A. R. Center | O. Center

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