TTVs are derived from Q1-Q16 Kepler data. x-axes: “Observed Tc” (Mid-Transit Time): EXOFAST’s best-fits from Kepler light flux vs. time data. y-axes: “(O – C)”: difference between Observed Tc and the Calculated Tc from the graphically obtained linear ephemeris. The plots are pictured in the order of orbital periods.
At present, KOI-880.01 (Kepler-82b) and KOI-880.02 (Kepler-82c) and confirmed exoplanets while KOI-880.03 and KOI-880.04 are candidates. The periods of the first two are in a MMR ratio of 2.000/1.026 but their TTV plots are not well anti-correlated and show somewhat different P_ttv values, suggesting that various degrees of orbital eccentricity exist for these two exoplanets.
1st Plot: KOI-880.04, P = 2.38 days [Plot error bars = ± 8.73 min.]
Linear ephemeris (this work): Tc = 2.38295404(Tc#) + 68.07986221
2nd Plot: KOI-880.03, P = 5.90 days [Plot error bars = ± 7.15 min.]
Linear ephemeris (this work): Tc = 5.90225894(Tc#) + 69.78364689
3rd Plot: KOI-880.01, P = 26.44 days [Plot error bars = ± 4.31 min.]
TTV_maximum: 99.63 ± 40.16 days, Amp_ttv_maximum: 19.80 ± 3.00 min.
TTV_minimum: 591.04 ± 47.19 days, Amp_ttv_minimum: -21.52 ± 3.00 min.
TTV_maximum: 1082.45 ± 60.95 days, Amp_ttv_maximum: 19.80 ± 3.00 min.