A Search for Additional Bodies in the GJ 1132 Planetary System from 21 Ground-based Transits and a 100 Hour Spitzer Campaign

Abstract

We present the results of a search for additional bodies in the GJ 1132 system through two methods: photometric transits and transit timing variations of the known planet. We collected 21 transit observations of GJ 1132b with the MEarth-South array since 2015. We obtained 100 near-continuous hours of observations with the $Spitzer$ Space Telescope, including two transits of GJ 1132b and spanning 60\% of the orbital phase of the maximum period at which bodies coplanar with GJ 1132b would pass in front of the star. We exclude transits of additional Mars-sized bodies, such as a second planet or a moon, with a confidence of 99.7\%. When we combine the mass estimate of the star (obtained from its parallax and apparent $K_s$ band magnitude) with the stellar density inferred from our high-cadence $Spitzer$ light curve (assuming zero eccentricity), we measure the stellar radius of GJ 1132 to be $0.2105_{-0.0085}^{+0.0102}{R}_{\odot }$, and we refine the radius measurement of GJ 1132b to $1.130\pm 0.056R_{\oplus }$. Combined with HARPS RV measurements, we determine the density of GJ 1132b to be $6.2\pm 2.0$\ g cm${}^{-3}$, with the mass determination dominating this uncertainty. We refine the ephemeris of the system and find no evidence for transit timing variations, which would be expected if there was a second planet near an orbital resonance with GJ 1132b.

arXiv comment29 pages, 4 Tables, 8 Figures, Submitted to ApJ. Comments welcome

References in corpus (44)

• emcee: The MCMC Hammer
• Analytic Lightcurves for Planetary Transit Searches
• Seven temperate terrestrial planets around the nearby ultracool dwarf star TRAPPIST-1
• batman: BAsic Transit Model cAlculatioN in Python
• A box-fitting algorithm in the search for periodic transits
• Clouds in the atmosphere of the super-Earth exoplanet GJ 1214b
• A super-Earth transiting a nearby low-mass star
• Most 1.6 Earth-Radius Planets are not Rocky
• Temperate Earth-sized planets transiting a nearby ultracool dwarf star
• The Solar Neighborhood XVII: Parallax Results from the CTIOPI 0.9m Program -- Twenty New Members of the RECONS 10 Parsec Sample
• Design Considerations for a Ground-based Transit Search for Habitable Planets Orbiting M dwarfs
• The Flat Transmission Spectrum of the Super-Earth GJ1214b from Wide Field Camera 3 on the Hubble Space Telescope
• A temperate rocky super-Earth transiting a nearby cool star
• Spitzer Secondary Eclipses of the Dense, Modestly-irradiated, Giant Exoplanet HAT-P-20b Using Pixel-Level Decorrelation
• A rocky planet transiting a nearby low-mass star
• The Mass of Kepler-93b and The Composition of Terrestrial Planets
• A combined transmission spectrum of the Earth-sized exoplanets TRAPPIST-1 b and c
• The Optical and Near-Infrared Transmission Spectrum of the Super-Earth GJ1214b: Further Evidence for a Metal-Rich Atmosphere
• Observational evidence for a metal rich atmosphere on the super-Earth GJ1214b
• Transit Detection in the MEarth Survey of Nearby M Dwarfs: Bridging the Clean-First, Search-Later Divide
• Predictions of the atmospheric composition of GJ 1132b
• ACCESS I: An Optical Transmission Spectrum of GJ 1214b Reveals a Heterogeneous Stellar Photosphere
• Habitable worlds with JWST: transit spectroscopy of the TRAPPIST-1 system?
• TTVFast: An efficient and accurate code for transit timing inversion problems
• The Kepler Dichotomy among the M Dwarfs: Half of Systems Contain Five or More Coplanar Planets
• Broadband Transmission Spectroscopy of the super-Earth GJ 1214b suggests a Low Mean Molecular Weight Atmosphere
• Kepler-445, Kepler-446 and the Occurrence of Compact Multiples Orbiting Mid-M Dwarf Stars
• The Transit Light Curve Project. XIII. Sixteen Transits of the Super-Earth GJ 1214b
• The Solar Neighborhood XIII: Parallax Results from the CTIOPI 0.9-m Program -- Stars with mu >= 1"/year (MOTION Sample)
• Identifying Planetary Biosignature Impostors: Spectral Features of CO and O4 Resulting from Abiotic O2/O3 Production
• High Resolution, Differential, Near-infrared Transmission Spectroscopy of GJ 1214b
• A Search for a Sub-Earth Sized Companion to GJ 436 and a Novel Method to Calibrate Warm Spitzer IRAC Observations
• Spitzer Transits of the Super-Earth GJ1214b and Implications for Its Atmosphere
• A 1.9 Earth radius rocky planet and the discovery of a non-transiting planet in the Kepler-20 system
• The Hunt for Exomoons with Kepler (HEK): IV. A Search for Moons around Eight M-Dwarfs
• On the relationship between the size and surface coverage of starspots on magnetically active low-mass stars
• Search for a habitable terrestrial planet transiting the nearby red dwarf GJ 1214
• A Tentative Detection of a Starspot During Consecutive Transits of an Extrasolar Planet from the Ground: No Evidence of a Double Transiting Planet System Around TrES-1
• Detection of the atmosphere of the 1.6 Earth mass exoplanet GJ 1132b
• Transit Timing Variations for Inclined and Retrograde Exoplanetary Systems
• Transit timing variations for planets near eccentricity-type mean motion resonances
• ExTrA: Exoplanets in Transit and their Atmospheres
• Search for Rayleigh scattering in the atmosphere of GJ1214b
• Narrow Band Halpha Photometry of the Super-Earth GJ 1214b with GTC/OSIRIS Tunable Filters

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