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.

1st Figure: KOI-464.02, P = 5.35 days [Plot avg. error bars = ± 4.68 min.]
Linear ephemeris (this work): Tc = 5.35016543(Tc#) + 128.76010842

2nd Figure: KOI-464.01, P = 58.36 days [Plot avg. error bars = ± 1.28 min.]
TTV_maximum: 214.68 ± 23.63 days, Amp_ttv_maximum: 3.98 ± 0.80 min.
TTV_minimum: 454.40 ± 26.16 days, Amp_ttv_minimum: -3.93 ± 0.80 min.
TTV_maximum: 694.13 ± 30.01 days, Amp_ttv_maximum: 3.98 ± 0.80 min.
TTV_minimum: 933.85 ± 34.75 days, Amp_ttv_minimum: -3.93 ± 0.80 min.
TTV_maximum: 1173.58 ± 40.06 days, Amp_ttv_maximum: 3.98 ± 0.80 min.
TTV_minimum: 1413.30 ± 45.74 days, Amp_ttv_minimum: -3.93 ± 0.80 min.
P_ttv: 479.45 ± 13.44 days.
Amp_ttv: 7.92 ± 1.13 minutes.
Lomb-Scargle periodogram, periodicity (P_ttv): 483.87 days; Power: 6.79; FAP: 0.000395.
Linear ephemeris (this work): Tc = 58.36205412(Tc#) + 129.55662974

Literature Tc#, Tc, and TTV Tabulations and References:
• For Q0-6 TTV data (thru ~ 563 (BJD-2454900) days): Ford et al., 2012, arXiv-1201.1892.
• For Q0-10 TTV data (thru ~ 934 (BJD-2454900) days): Rowe et al., 2014, arXiv-1402.6534.
• For Q0-12 TTV data (thru ~ 1116 (BJD-2454900) days): Mazeh et al., 2013, arXiv-1301.5499.
• For Q0-12 Calc. properties from TTVs: Hadden & Lithwick, 2013, arXiv-1310.7942.
• For Q0-13/14 TTV data, Xie: http://www.astro.utoronto.ca/~jwxie/TTV/TTV_Home.html
• Two ground-based Kepler-TTV-follow-up programs are in place at the moment: --- Gary, "KAFO" project: http://brucegary.net/kafo/ --- von Essen, "KOINet": http://koinet.astro.physik.uni-goettingen.de/

7 May 2014

Exoplanet-Science.com

Kepler KOI-464 (KIC-8890783) 3-(or more?)-Planet System

TTV Evidence:
The presence of both a credible (i.e.: False Alarm Probability (FAP) < 0.1) periodicity in the Lomb-Scargle Periodogram (LSP) of [(O-C) vs. Time] ("TTVxy") data points, along with a sinusoidal distribution of the same points displaying a closely corresponding periodicity ("P_ttv") (see Figure(s) below), is strongly suggestive of the presence of an unseen (non-transiting), gravitationally perturbing planetary object(s) in this system.

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KOI's (Blue)  or
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