Stellar Companions of Exoplanet Host Stars in K2

Abstract

It is well established that roughly half of all nearby solar-type stars have at least one companion. Stellar companions can have significant implications for the detection and characterization of exoplanets, including triggering false positives and masking the true radii of planets. Determining the fraction of exoplanet host stars that are also binaries allows us to better determine planetary characteristics as well as establish the relationship between binarity and planet formation. Using high angular resolution speckle imaging, we detect stellar companions within ~1 arcsec of K2 planet candidate host stars. Comparing our detected companion rate to TRILEGAL star count simulations and known detection limits of speckle imaging we estimate the binary fraction of K2 planet host stars to be 40 - 50%, similar to that of Kepler exoplanet hosts and field stars.

arXiv commentAccepted for publication in The Astronomical Journal. 18 pages, 9 figures, 3 tables

References in corpus (26)

• A Survey of Stellar Families: Multiplicity of Solar-Type Stars
• The K2 Mission: Characterization and Early results
• Stellar Multiplicity
• Star counts in the Galaxy. Simulating from very deep to very shallow photometric surveys with the TRILEGAL code
• Terrestrial Planet Occurrence Rates for the Kepler GK Dwarf Sample
• The K2 Ecliptic Plane Input Catalog (EPIC) and Stellar Classifications of 138,600 Targets in Campaigns 1-8
• Understanding The Effects Of Stellar Multiplicity On The Derived Planet Radii From Transit Surveys: Implications for Kepler, K2, and TESS
• The Impact of Stellar Multiplicity on Planetary Systems, I.: The Ruinous Influence of Close Binary Companions
• The Kepler Follow-Up Observation Program. I. A Catalog of Companions to Kepler Stars from High-Resolution Imaging
• Planetary Candidates from the First Year of the K2 Mission
• 197 Candidates and 104 Validated Planets in K2's First Five Fields
• Expected Detection and False Alarm Rates for Transiting Jovian Planets
• Influence of Stellar Multiplicity On Planet Formation. I. Evidence of Suppressed Planet Formation Due to Stellar Companions Within 20 AU and Validation of Four Planets From the Kepler Multiple Planet Candidates
• Influence of Stellar Multiplicity On Planet Formation. II. Planets Are Less Common in Multiple-Star Systems with Separations Smaller than 1500 AU
• Most Sub-Arcsecond Companions of Kepler Exoplanet Candidate Host Stars are Gravitationally Bound
• Characterizing K2 Candidate Planetary Systems Orbiting Low-Mass Stars II: Planetary Systems Observed During Campaigns 1-7
• On the Likelihood of Planet Formation in Close Binaries
• High-resolution Multi-band Imaging for Validation and Characterization of Small Kepler Planets
• Planet formation in stellar binaries II: overcoming the fragmentation barrier in alpha Centauri and gamma Cephei-like systems
• Planet formation in Binaries
• Planet formation in stellar binaries I: planetesimal dynamics in massive protoplanetary disks
• Dynamical Stability and Habitability of Gamma Cephei Binary-Planetary System
• The Densities of Planets in Multiple Stellar Systems
• Assessing the Effect of Stellar Companions from High-Resolution Imaging of Kepler Objects of Interest
• Speckle Imaging Excludes Low-Mass Companions Orbiting the Exoplanet Host Star TRAPPIST-1
• A Pan-STARRS1 study of the relationship between wide binarity and planet occurrence in the Kepler field

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• The First Habitable Zone Earth-sized Planet from TESS. I: Validation of the TOI-700 System
• Three Red Suns in the Sky: A Transiting, Terrestrial Planet in a Triple M Dwarf System at 6.9 Parsecs
• Speckle Observations of TESS Exoplanet Host Stars. II. Stellar Companions at 1-1000 AU and Implications for Small Planet Detection
• Understanding the Impacts of Stellar Companions on Planet Formation and Evolution: A Survey of Stellar and Planetary Companions within 25 pc
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• A pair of Sub-Neptunes transiting the bright K-dwarf TOI-1064 characterised with CHEOPS
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• Speckle Observations of TESS Exoplanet Host Stars: Understanding the Binary Exoplanet Host Star Orbital Period Distribution
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• TOI-2109b: An Ultrahot Gas Giant on a 16 hr Orbit
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• A Closer Look at Exoplanet Occurrence Rates: Considering the Multiplicity of Stars Without Detected Planets
• TOI-530b: A giant planet transiting an M dwarf detected by TESS
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• The TESS Grand Unified Hot Jupiter Survey. II. Twenty New Giant Planets
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• Observations of Binary Stars with the Differential Speckle Survey Instrument. IX. Observations of Known and Suspected Binaries, and a Partial Survey of Be Stars
• The Effects of Stellar Companions on Exoplanet Radius Distributions
• Scaling K2. IV. A Uniform Planet Sample for Campaigns 1-8 and 10-18
• Detecting Unresolved Binaries in TESS Data with Speckle Imaging
• Scaling K2. II. Assembly of a Fully Automated C5 Planet Candidate Catalog Using EDI-Vetter
• Observations of Binary Stars with the Differential Speckle Survey Instrument. VIII. Measures of Metal-Poor Stars and Triple Stars from 2015 to 2018
• Demographics of Exoplanets in Binaries (DEB). I. Architecture of S-Type Planetary Systems Revealed by the RV Sample
• The TESS Grand Unified Hot Jupiter Survey. I. Ten TESS Planets
• Orbital elements and individual component masses from joint spectroscopic and astrometric data of double-line spectroscopic binaries
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• Scaling K2. III. Comparable Planet Occurrence in the FGK Samples of Campaign 5 and Kepler
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• Validation and atmospheric exploration of the sub-Neptune TOI-2136b around a nearby M3 dwarf
• TESS Giants Transiting Giants V -- Two hot Jupiters orbiting red-giant hosts
• TOI-4336 A b: A temperate sub-Neptune ripe for atmospheric characterization in a nearby triple M-dwarf system
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• Revised Properties and Dynamical History for the HD 17156 System
• The Hot-Neptune Initiative (HONEI) I. Two hot sub-Neptunes on a close-in, eccentric orbit (TOI-5800 b) and a farther-out, circular orbit (TOI-5817 b)
• TESS Discovery of Twin Planets near 2:1 Resonance around Early M-Dwarf TOI 4342
• Stellar Obliquity Excitation via Disk Dispersal-Driven Resonances in Binaries
• Migration and Evolution of giant ExoPlanets (MEEP) II: Super-Jupiters and Lithium-rich Host Stars
• K2 Targets Observed with SPHERE/VLT: An M4-7 Dwarf Companion Resolved around EPIC 206011496
• Giant Outer Transiting Exoplanet Mass (GOT 'EM) Survey. VI: Confirmation of a Long-Period Giant Planet Discovered with a Single TESS Transit
• TOI-1199 b and TOI-1273 b: Two new transiting hot Saturns detected and characterized with SOPHIE and TESS
• BD-14 3065b (TOI-4987b): from giant planet to brown dwarf: evidence for deuterium burning in old age?
• TOI-2322: two transiting rocky planets close to the stellar rotation period and its first harmonic
• Detection and characterisation of a 106-day transiting Jupiter : TOI-2449 b / NGTS-36 b
• Joint Analysis of Multicolor Photometry: A New Approach to Constrain the Nature of Multiple-Star Systems Hosting Exoplanet Candidates
• TIC 172900988: A Transiting Circumbinary Planet Detected in One Sector of TESS Data
• Detection and characterisation of two VLM binaries: LP 1033-31 and LP 877-72
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• ASTEP confirmation of a pair of long-period Jupiter-sized planets with extremely low densities transiting TOI-791
• TOI-1438: A rare system with two short-period sub-Neptunes and a tentative long-period Jupiter-like planet orbiting a K0V star