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                 Kepler KOI-1772 (KIC-3345675) 2-(or more?)-Planet System

Discussion:
A sinusoidal curve-fit of the [(O-C) vs. Time] data for KOI-1772.01 showed (Figure below) a periodicity (P_ttv) of 1337.38 ± 229.81 days; a Lomb-Scargle Periodogram (LSP) of the same data gave a medium-credibility periodicity of 1613.98 days.  Potentially, one other non-transiting planet is gravitationally interacting with KOI-1772.01 in this stellar system.
The just ~ 1 sinusoidal cycle variation observed during Kepler’s “precision-lifetime” is responsible for the sizeable differences found for the P_ttv determined by the above-mentioned two methods.

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: KOI-1772.01, P = 120.00 days [Plot avg. error bars = ± 0.69 min.]
TTV_maximum: 242.93 ± 165.24 days, Amp_ttv_maximum: 4.89 ± 1.89 min.
TTV_minimum: 911.62 ± 223.83 days, Amp_ttv_minimum: -7.66 ± 1.89 min.
P_ttv: 1337.38 ± 229.81 days.
Amp_ttv: 12.55 ± 2.67 minutes.
Lomb-Scargle periodogram, candidate P_ttv: 1613.98 days; Power: 3.55; FAP: 0.0258.
Linear ephemeris (this work): Tc = [120.00322792 ± 0.00031589](Tc#) + [183.14176515 ± 0.00212842]


Numerous literature and major Tc#, Tc, and TTV tabulation references can be found on my "Summary" webpage following the table.

29 May 2015