False Positive Probabilities for All Kepler Objects of Interest: 1284 Newly Validated Planets and 428 Likely False Positives

Abstract

We present astrophysical false positive probability calculations for every Kepler Object of Interest (KOI)-the first large-scale demonstration of a fully automated transiting planet validation procedure. Out of 7056 KOIs, we determine that 1935 have probabilities <1% to be astrophysical false positives, and thus may be considered validated planets. 1284 of these have not yet been validated or confirmed by other methods. In addition, we identify 428 KOIs likely to be false positives that have not yet been identified as such, though some of these may be a result of unidentified transit timing variations. A side product of these calculations is full stellar property posterior samplings for every host star, modeled as single, binary, and triple systems. These calculations use vespa, a publicly available Python package able to be easily applied to any transiting exoplanet candidate.

Precise radial velocities of giant stars

“…Of these planets, about 75% have been discovered by the transit method, which has greatly benefited from the data obtained with the Kepler Space Telescope (Borucki et al 2010). Moreover, in 2014 alone, 715 new planets in 305 systems were detected by Kepler, almost doubling the number of exoplanets known at that time (Lissauer et al 2014;Rowe et al 2014), and more recently, Morton et al (2016) have confirmed nearly 1280 new transiting Kepler planets based on probabilistic validation methods. Most of the remaining 25% of planets have been found using the radial velocity (RV) technique.…”

Dependence of Small Planet Frequency on Stellar Metallicity Hidden by Their Prevalence

“…This became possible only recently thanks to the Kepler Space Telescope (Borucki et al 2010). Thousands of small planet candidates have been detected by Kepler (Borucki et al 2011a,b;Batalha et al 2013;Burke et al 2014;Rowe et al 2015;Mullally et al 2015;Coughlin et al 2015), and the majority of them are either confirmed or believed to be bona fide planets (e.g., Fressin et al 2013;Lissauer et al 2012;Morton et al 2016). Several studies have been conducted to investigate the small planet-metallicity correlation based on the Kepler planet catalog.…”

Three Statistically Validated K2 Transiting Warm Jupiter Exoplanets Confirmed as Low-mass Stars

“…That upper limit is typically at the 1% or 0.1% level in order to declare a candidate as a validated planet (e.g., Montet et al 2015;Crossfield et al 2016;Morton et al 2016). Hence, the validated planets have measured orbital periods and radii, but their masses are unknown.…”

“…Those candidates need to be examined by gathering additional data, to check whether the transit light curve is produced by a transiting star-planet system, or by a different scenario, making the object a false positive (e.g., Torres et al 2011;Fressin et al 2013). As there are insufficient observational resources needed for gathering the amount of data required to investigate the true nature of each transiting planet candidate, and because some planets cannot be confirmed with current observational capabilities, a statistical validation approach was developed (e.g., Torres et al 2011Torres et al , 2015Morton et al 2016). This approach uses a relatively small amount of observational follow-up data, typically including a single spectrum and a single high angular resolution image of the target, and is based on estimating the probability that the transit light curve is produced by a transiting star-planet system and not a false-positive scenario (e.g., Torres et al 2011;Morton 2012).…”