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Title: Photo-dynamical analysis of three Kepler objects of interest with significant transit timing variations

Abstract

KOI-227, KOI-319 and KOI-884 are identified here as (at least) two planet systems. For KOI-319 and KOI-884, the observed Transit Timing Variations (TTVs) of the inner transiting planet are used to detect an outer non-transiting planet. The outer planet in KOI-884 is ≅2.6 Jupiter masses and has the orbital period just narrow of the 3:1 resonance with the inner planet (orbital period ratio 2.93). The distribution of parameters inferred from KOI-319.01's TTVs is bimodal with either a ≅1.6 Neptune-mass (M{sub N}) planet wide of the 5:3 resonance (period 80.1 days) or a ≅1 Saturn-mass planet wide of the 7:3 resonance (period 109.2 days). The radial velocity measurements can be used in this case to determine which of these parameter modes is correct. KOI-227.01's TTVs with large ≅10 hr amplitude can be obtained for planetary-mass companions in various major resonances. Based on the Bayesian evidence, the current TTV data favor the outer 2:1 resonance with a companion mass ≅1.5 M{sub N}, but this solution implies a very large density of KOI-227.01. The inner and outer 3:2 resonance solutions with sub-Neptune-mass companions are physically more plausible, but will need to be verified.

Authors:
;  [1];  [2];  [3]
  1. Department of Space Studies, Southwest Research Institute, Boulder, CO 80302 (United States)
  2. Harvard-Smithsonian Center for Astrophysics, Cambridge, MA 02138 (United States)
  3. Cavendish Laboratory, University of Cambridge, Cambridge CB3 0HE (United Kingdom)
Publication Date:
OSTI Identifier:
22365605
Resource Type:
Journal Article
Resource Relation:
Journal Name: Astrophysical Journal; Journal Volume: 790; Journal Issue: 1; Other Information: Country of input: International Atomic Energy Agency (IAEA)
Country of Publication:
United States
Language:
English
Subject:
79 ASTROPHYSICS, COSMOLOGY AND ASTRONOMY; AMPLITUDES; DENSITY; DETECTION; DISTRIBUTION; MASS; RADIAL VELOCITY; RESONANCE; SATELLITES; STABILITY

Citation Formats

Nesvorný, David, Terrell, Dirk, Kipping, David, and Feroz, Farhan. Photo-dynamical analysis of three Kepler objects of interest with significant transit timing variations. United States: N. p., 2014. Web. doi:10.1088/0004-637X/790/1/31.
Nesvorný, David, Terrell, Dirk, Kipping, David, & Feroz, Farhan. Photo-dynamical analysis of three Kepler objects of interest with significant transit timing variations. United States. doi:10.1088/0004-637X/790/1/31.
Nesvorný, David, Terrell, Dirk, Kipping, David, and Feroz, Farhan. 2014. "Photo-dynamical analysis of three Kepler objects of interest with significant transit timing variations". United States. doi:10.1088/0004-637X/790/1/31.
@article{osti_22365605,
title = {Photo-dynamical analysis of three Kepler objects of interest with significant transit timing variations},
author = {Nesvorný, David and Terrell, Dirk and Kipping, David and Feroz, Farhan},
abstractNote = {KOI-227, KOI-319 and KOI-884 are identified here as (at least) two planet systems. For KOI-319 and KOI-884, the observed Transit Timing Variations (TTVs) of the inner transiting planet are used to detect an outer non-transiting planet. The outer planet in KOI-884 is ≅2.6 Jupiter masses and has the orbital period just narrow of the 3:1 resonance with the inner planet (orbital period ratio 2.93). The distribution of parameters inferred from KOI-319.01's TTVs is bimodal with either a ≅1.6 Neptune-mass (M{sub N}) planet wide of the 5:3 resonance (period 80.1 days) or a ≅1 Saturn-mass planet wide of the 7:3 resonance (period 109.2 days). The radial velocity measurements can be used in this case to determine which of these parameter modes is correct. KOI-227.01's TTVs with large ≅10 hr amplitude can be obtained for planetary-mass companions in various major resonances. Based on the Bayesian evidence, the current TTV data favor the outer 2:1 resonance with a companion mass ≅1.5 M{sub N}, but this solution implies a very large density of KOI-227.01. The inner and outer 3:2 resonance solutions with sub-Neptune-mass companions are physically more plausible, but will need to be verified.},
doi = {10.1088/0004-637X/790/1/31},
journal = {Astrophysical Journal},
number = 1,
volume = 790,
place = {United States},
year = 2014,
month = 7
}
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