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TTVs are derived from Q1-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.

Figure 1.: KOI-872.01, P = 33.60 days [Plot avg. error bars = ± 1.63 min. (smaller than symbols)]
TTV_maximum: 127.58 ± 4.52 days, Amp_ttv_maximum: 52.55 ± 4.65 min.
TTV_minimum: 222.42 ± 4.62 days, Amp_ttv_minimum: -55.12 ± 4.65 min.
TTV_maximum: 317.25 ± 4.77 days, Amp_ttv_maximum: 52.55 ± 4.65 min.
TTV_minimum: 412.08 ± 4.97 days, Amp_ttv_minimum: -55.12 ± 4.65 min.
--- (4 intervening maxima and 3 intervening minima) ---
TTV_minimum: 1170.72 ± 7.61 days, Amp_ttv_minimum: -55.12 ± 4.65 min.
TTV_maximum: 1265.55 ± 8.02 days, Amp_ttv_maximum: 52.55 ± 4.65 min.
TTV_minimum: 1360.38 ± 8.44 days, Amp_ttv_minimum: -55.12 ± 4.65 min.
TTV_maximum: 1455.21 ± 8.86 days, Amp_ttv_maximum: 52.55 ± 4.65 min.
P_ttv: 189.66 ± 1.00 days.
Amp_ttv: 107.67 ± 6.58 minutes.
Lomb-Scargle periodogram, candidate P_ttv: 189.30 days; Power: 15.83; FAP: 4.197 x 10^-14.
Linear ephemeris (this work): Tc = 33.60121764(Tc#) + 119.68149151

Figure 2.: Residuals of Figure 1. [Plot avg. error bars = ± 4.93 min.]
TTV_maximum: 87.46 ± 3.84 days, Amp_ttv_maximum: 17.46 ± 3.01 min.
TTV_minimum: 128.26 ± 3.86 days, Amp_ttv_minimum: -17.62 ± 3.01 min.
TTV_maximum: 169.07 ± 3.89 days, Amp_ttv_maximum: 17.46 ± 3.01 min.
TTV_minimum: 209.87 ± 3.93 days, Amp_ttv_minimum: -17.62 ± 3.01 min.
--- (13 intervening maxima and 13 intervening minima) ---
TTV_maximum: 1455.21 ± 8.86 days, Amp_ttv_maximum: 17.46 ± 3.01 min.
TTV_minimum: 1170.72 ± 7.61 days, Amp_ttv_minimum: -17.62 ± 3.01 min.
TTV_maximum: 1265.55 ± 8.02 days, Amp_ttv_maximum: 17.46 ± 3.01 min.
TTV_minimum: 1360.38 ± 8.44 days, Amp_ttv_minimum: -17.62 ± 3.01 min.
P_ttv: 81.60 ± 0.36 days.
Amp_ttv: 35.08 ± 4.25 minutes.
Lomb-Scargle periodogram, candidate P_ttv: 81.52 days; Power: 11.08; FAP: 2.633 x 10^-6.

Figure 3.: Residuals of Figure 2. [Plot avg. error bars = ± 5.78 min.]
TTV_minimum: 147.96 ± 7.96 days, Amp_ttv_minimum: -9.42 ± 2.13 min.
TTV_maximum: 220.07 ± 8.09 days, Amp_ttv_maximum: 11.48 ± 2.13 min.
TTV_minimum: 292.18 ± 8.26 days, Amp_ttv_minimum: -9.42 ± 2.13 min.
TTV_maximum: 364.29 ± 8.49 days, Amp_ttv_maximum: 11.48 ± 2.13 min.
--- (5 intervening maxima and 6 intervening minima) ---
TTV_maximum: 1229.62 ± 13.42 days, Amp_ttv_maximum: 11.48 ± 2.13 min.
TTV_minimum: 1301.73 ± 13.94 days, Amp_ttv_minimum: -9.42 ± 2.13 min.
TTV_maximum: 1373.84 ± 14.47 days, Amp_ttv_maximum: 11.48 ± 2.13 min.
TTV_minimum: 1445.95 ± 15.01 days, Amp_ttv_minimum: -9.42 ± 2.13 min.
P_ttv: 144.22 ± 1.28 days.
Amp_ttv: 20.91 ± 3.01 minutes.
Lomb-Scargle periodogram, candidate P_ttv: 144.38 days; Power: 9.30; FAP: 1.033 x 10^-4.
(also a 2nd weaker periodicity is evident: P_ttv: 530.85 days;  Power: 4.87; FAP: 9.599 x 10^-2.)

Figure 4.: Residuals of Figure 3. [Plot avg. error bars = ± 6.15 min.]
TTV_minimum: 145.21 ± 38.05 days, Amp_ttv_minimum: -6.45 ± 1.59 min.
TTV_maximum: 417.69 ± 41.45 days, Amp_ttv_maximum: 6.52 ± 1.59 min.
TTV_minimum: 690.18 ± 47.42 days, Amp_ttv_minimum: -6.45 ± 1.59 min.
TTV_maximum: 962.66 ± 55.14 days, Amp_ttv_maximum: 6.52 ± 1.59 min.
TTV_minimum: 1235.15 ± 63.98 days, Amp_ttv_minimum: -6.45 ± 1.59 min.
P_ttv: 544.97 ± 22.85 days.
Amp_ttv: 12.97 ± 2.25 minutes.
Lomb-Scargle periodogram, candidate P_ttv: 541.59 days; Power: 7.92; FAP: 1.414 x 10^-3.

Figure 5.: Added combination of Figures 1., 2., 3., and 4. [Plot (purple) error bars = ± 9.91 min.]

Figure 6.: KOI-872.02, P = 6.77 days [Plot avg. error bars = ± 9.65 min. (smaller than symbols)]
Lomb-Scargle periodogram, most prominent P_ttv: 81.98 days; Power: 7.59; FAP: 0.574.
Linear ephemeris (this work): Tc = 6.76651806(Tc#) + 71.06606947

• Nesvorny, Kipping, Buchhave, Bakos, Hartman, and Schmitt, arXiv:1208.0942v1 [astro-ph.EP] 4 Aug 2012.
• For other literature Tc#, Tc, and TTV Major Tabulations and Other References: see my "Summary" webpage.

30 Sep 2014
For completeness, Figure 7. shows the [Time vs. (O-C)] data for the closer-in planet in this system, 872.02, but no clear TTV.  Further, while no low FAP periodicity was found in 872.02's Lomb-Scargle periodogram, the most prominent peak in the latter occurred at 81.98 days (FAP of only 0.574) which (not coincidentally) does correspond to the observed credible 81.60 days for 872.01's TTV-1st-Residuals.
Figure 1.: 872.01's [Time vs. (O-C)] data and, from the best-fit sinusoid, its primary P_ttv and Amp_ttv.
Figure 2.: Residuals from Figure 1. and their corresponding periodicities.
Figure 3.: Residuals from Figure 2. and their corresponding periodicities.
Figure 4.: Residuals from Figure 3. and their corresponding periodicities.
Figure 5.: Summed array of all four component sinusoids and the resulting close agreement with the initial (Figure 1.) data points.
Larger errors were found for transit durations (since they include large errors for ingress and egress) than for the Times of Full Width at Half Maximum (T_{FWHM}), i.e., the times between the center of the planet crossing each of the star's limbs.  T_{FWHM} plotted vs. Time for 872.01, with both LC and SC data (see Figure 6.), shows a gradual increase with time, possibly implying that its orbit has some eccentricity and it is slowly precessing.
KOI-872 (Kepler-46, KIC-7109675) 3-(or more?)-Planets

Discussion:
In their seminal paper, Nesvorny, Kipping, Buchhave, Bakos, Hartman, and Schmitt, 2012 (ref. below), using only long-cadence (LC) Kepler data from Q1-Q6, reported that KOI-872.01 exhibited a large (~ 2 hours) and complex TTV, with a dominant periodicity of ~ 190 days, from which they then calculated some properties of an unseen planetary perturber.  Revisiting this system now using LC data available for Q1-Q17 as well as short-cadence (SC) data available for Q7-Q10 & Q12-Q17, it appears, among other things, that the TTV of this system is, indeed, extremely complex.
After a sinusoidal curve-fit of the [Time vs. (O-C)] data of 872.01 showed (Figure 1. below) a periodicity (P_ttv) of 189.66 ± 1.00 days with an amplitude of 107.67 ± 6.58 minutes (189.29 days was the credible periodicity observed in the Lomb-Scargle Periodogram (LSP) of the same data), a plot (Figure 2.) of the Residuals also gave a good sinusoidal curve-fit with a periodicity of 81.60 ± 0.36 days (LSP: 81.52 days).  Similarly, the Residuals-of-the-Residuals gave a good sinusoidal curve-fit (Figure 3.) with a periodicity of 144.22 ± 1.28 days (LSP: 144.37 days).  In addition, the Residuals-of-the-Residuals-of-the-Residuals gave a good sinusoidal curve-fit (Figure 4.) with a periodicity of 544.97 ± 22.85 days (LSP: 541.59 days).  As expected, the amplitudes within this series of periodicities decreased monotonically: 107.67, 35.08, 20.91, and 12.97 minutes, respectively.  All of the Lomb-Scargle periodicities, from their low False Alarm Probability (FAP) (see data below), appeared to be highly credible; they ranged from ~ 10^-14 to ~ 10^-3.
Finally, the summed combination of all four of these sinusoidal arrays is shown in Figure 5.  Note that the initial data points from Figure 1. (re-plotted here) agree quite closely with the resulting complex overall curvature.
Numerous effects could be responsible for these "teased-apart" overlapping sinusoidal arrays.  Among them are:
• mutual gravitational interaction of 872.01 with 872.02;
• mutual gravitational interaction(s) 872.01 with unseen (non-transiting or undetected) planet(s);
• orbital eccentricity(ies);
• orbital precession(s); and/or
• large exomoon(s).