TTVs are derived from Q0-Q17 Kepler data. x-axes: “Observed Tc” (Mid-Transit Time): EXOFAST’s best-fits from Normalized PDCSAP_FLUX Kepler light flux vs. time (BJD_tdb - 2454900) data. y-axes: “(O-C)”: difference between Observed Tc and the Calculated Tc from the graphically obtained linear ephemeris.
Related TTV Tabulations and References: • For Q0-6 TTV data (thru ~ 563 (BJD-2454900) days): Ford et al., 2012, arXiv-1201.1892. • For Q0-10 TTV data (thru ~ 934 (BJD-2454900) days): Rowe et al., 2014, arXiv-1402.6534. • For Q0-12 TTV data (thru ~ 1116 (BJD-2454900) days): Mazeh et al., 2013, arXiv-1301.5499. • For Q0-12 Calc. properties from TTVs: Hadden & Lithwick, 2013, arXiv-1310.7942. • For Q0-13/14 TTV data, Xie: http://www.astro.utoronto.ca/~jwxie/TTV/TTV_Home.html • Two ground-based Kepler-TTV-follow-up programs are in place at the moment: --- Gary, "KAFO" project: http://brucegary.net/kafo/ --- von Essen, "KOINet": http://koinet.astro.physik.uni-goettingen.de/
28 Apr 2014
Kepler KOI-4235.01 (KIC-10794974) 2-(or more?)-Planet System
TTV Evidence: The presence of both a credible (i.e.: False Alarm Probability (FAP) < 0.1) periodicity in the Lomb-Scargle Periodogram (LSP) of [(O-C) vs. Time] ("TTVxy") data points, along with a sinusoidal distribution of the same points displaying a closely corresponding periodicity ("P_ttv") (see Figure(s) below), is strongly suggestive of the presence of an unseen (non-transiting), gravitationally perturbing planetary object(s) in this system.