High-resolution Multi-band Imaging for Validation and Characterization of Small Kepler Planets

Abstract

High-resolution ground-based optical speckle and near-infrared adaptive optics images are taken to search for stars in close angular proximity to host stars of candidate planets identified by the NASA Kepler Mission. Neighboring stars are a potential source of false positive signals. These stars also blend into Kepler light curves, affecting estimated planet properties, and are important for an understanding of planets in multiple star systems. Deep images with high angular resolution help to validate candidate planets by excluding potential background eclipsing binaries as the source of the transit signals. A study of 18 Kepler Object of Interest stars hosting a total of 28 candidate and validated planets is presented. Validation levels are determined for 18 planets against the likelihood of a false positive from a background eclipsing binary. Most of these are validated at the 99% level or higher, including 5 newly-validated planets in two systems: Kepler-430 and Kepler-431. The stellar properties of the candidate host stars are determined by supplementing existing literature values with new spectroscopic characterizations. Close neighbors of 7 of these stars are examined using multi-wavelength photometry to determine their nature and influence on the candidate planet properties. Most of the close neighbors appear to be gravitationally-bound secondaries, while a few are best explained as closely co-aligned field stars. Revised planet properties are derived for each candidate and validated planet, including cases where the close neighbors are the potential host stars.

in press at AJ, 44 pages, 8 figures; The only changes made relative to version 1 are updates to the list of references

References in corpus (4)

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Cited by in corpus (13)

• The Kepler Follow-Up Observation Program. I. A Catalog of Companions to Kepler Stars from High-Resolution Imaging
• HEK VI: On the Dearth of Galilean Analogs in Kepler and the Exomoon Candidate Kepler-1625b I
• Assessing the Effect of Stellar Companions from High-Resolution Imaging of Kepler Objects of Interest
• HATS-9b and HATS-10b: Two Compact Hot Jupiters in Field 7 of the K2 Mission
• Unresolved Binary Exoplanet Host Stars Fit as Single Stars: Effects on the Stellar Parameters
• A Closer Look at Exoplanet Occurrence Rates: Considering the Multiplicity of Stars Without Detected Planets
• Detection of Planetary and Stellar Companions to Neighboring Stars via a Combination of Radial Velocity and Direct Imaging Techniques
• Revising Properties of Planet-Host Binary Systems. III. There is No Observed Radius Gap For Kepler Planets in Binary Star Systems
• Identifying Bound Stellar Companions to Kepler Exoplanet Host Stars Using Speckle Imaging
• Stellar Companions to the Exoplanet Host Stars HD 2638 and HD 164509
• Exclusion of Stellar Companions to Exoplanet Host Stars
• Revising Properties of Planet-host Binary Systems II: Apparent Near-Earth Analog Planets in Binaries Are Often Sub-Neptunes
• The Robo-AO KOI Survey: laser adaptive optics imaging of every Kepler exoplanet candidate