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.
2nd Figure., KOI-3791.01, P = 440.79 days [Plot avg. error bars = ± 2.21 min.] TTV_maximum: ~ 186.68 days, Amp_ttv_maximum: ~ 8.17 min. TTV_minimum: ~ 788.61 days, Amp_ttv_minimum: ~ -13.94 min. TTV_maximum: ~ 1390.53 days, Amp_ttv_maximum: ~ 8.17 min. P_ttv: ~ 1203.85 days. Amp_ttv: ~ 22.12 minutes. Linear ephemeris (this work): Tc = 440.78415930(Tc#) + 72.35846880
Numerous literature and major Tc#, Tc, and TTV tabulation references can be found on my "Summary" webpage following the table.
6 Oct 2014
Kepler KOI-3791 (KIC-5437945) 2-Planet System
Discussion: When periodicity values from both sinusoidal best-fits of [(O-C) vs. Time] data and Lomb-Scargle Periodograms of the same data are substantial and visually obvious, they may not correspond very closely* if only one cycle of periodicity has been observed. Further, as in this case, this result can also obtain if very few data points are available*. An important TTV-confirming observation in this case is that a strong anti-correlation exists (see following figures) between them.