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Exoplanet-Science.com

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.

Discussion:
The observed sinusoidal TTV of 1871.01 suggests the presence of another unseen (non-transiting) exoplanet in this system.


1st: KOI-1871.02, P = 32.38 days [Plot error bars = ± 6.41 min.]
Linear ephemeris (this work): Tc = 32.37635619(Tc#) + 83.41232325

2nd: KOI-1871.01, P = 92.73 days [Plot error bars = ± 5.94 min.]

TTV_maximum: 174.21 ± 56.29 days, Amp_ttv_maximum: 11.12 ± 3.52 min.
TTV_minimum: 488.97 ± 63.94 days, Amp_ttv_minimum: -14.10 ± 3.52 min.
TTV_maximum: 803.74 ± 76.70 days, Amp_ttv_maximum: 11.12 ± 3.52 min.
TTV_minimum: 1118.51 ± 92.46 days, Amp_ttv_minimum: -14.10 ± 3.52 min.
P_ttv: 629.54 ± 41.80 days.
Amp_ttv: 25.22 ± 4.97 minutes.
Lomb-Scargle periodogram, candidate P_ttv: 627.23 days; Power: 4.11; P-value: 0.0216.
Estimated P_ttv (given nearMMR of 3/1; ref. below): 682.46 days
Linear ephemeris (this work): Tc = 92.72987484(Tc#) + 110.44286448


References:
• Fabrycky et al., arXiv-1201.5415; P_ttv = 1/|(nmmri_a/P_a - nmmri_b/P_b)|.
• For Q0-Q6 TTV data of 1871.01 (thru ~ 563 (BJD-2454900) days), see: Ford et al., 2012, arXiv-1201.1892.
• For Q0-12 TTV data of 1871.01 (thru ~ 1116 (BJD-2454900) days), see: Mazeh et al., 2013, arXiv-1301.5499.

20 Dec 2013
Kepler KOI-1871 (KIC-9758089) 3-(or more?)-Planet System