SOPHIE velocimetry of Kepler transit candidates. VIII. KOI-205 b: a brown-dwarf companion to a K-type dwarf

Abstract

We report the discovery of a transiting brown dwarf companion to KOI-205, a K0 main-sequence star, in a 11.720125-day period orbit. The transits were detected by the Kepler space telescope, and the reflex motion of the star was measured using radial velocity observations obtained with the SOPHIE spectrograph. The atmospheric parameters of the host stars were determined from the analysis of high-resolution, high signal-to-noise ratio ESPaDOns spectra obtained for this purpose. Together with spectrophotometric measurements recovered from the literature, these spectra indicate that the star is a mildly metallic K0 dwarf with Teff 5237 $\pm$ 60 K. The mass of the companion is 39.9 $\pm$ 1.0 MJup and its radius is 0.81 $\pm$ 0.02 RJup, in agreement with current theoretical predictions. This is the first time a bona fide brown dwarf companion is detected in orbit around a star of this type. The formation and orbital evolution of brown dwarf companions is briefly discussed in the light of this new discovery.

arXiv comment4 pages, accepted for publication in A&A

References in corpus (30)

• Cosmological parameters from SDSS and WMAP
• Evolutionary models for cool brown dwarfs and extrasolar giant planets. The case of HD 20945
• Models of Stars, Brown Dwarfs and Exoplanets
• No planet for HD 166435
• Stellar, brown dwarf and multiple star properties from a radiation hydrodynamical simulation of star cluster formation
• Improving the Efficiency of Markov Chain Monte Carlo for Analyzing the Orbits of Extrasolar Planets
• Origins of Eccentric Extrasolar Planets: Testing the Planet-Planet Scattering Model
• The properties of brown dwarfs and low-mass hydrogen-burning stars formed by disc fragmentation
• The Transit Light Curve Project. IX. Evidence for a Smaller Radius of the Exoplanet XO-3b
• Binning is sinning: morphological light-curve distortions due to finite integration time
• KELT-1b: A Strongly Irradiated, Highly Inflated, Short Period, 27 Jupiter-mass Companion Transiting a mid-F Star
• Thermohaline instability and rotation-induced mixing. III - Grid of stellar models and asymptotic asteroseismic quantities from the pre-main sequence up to the AGB for low- and intermediate-mass stars at various metallicities
• Kepler Mission Stellar and Instrument Noise Properties
• Transiting exoplanets from the CoRoT space mission VI. CoRoT-Exo-3b: The first secure inhabitant of the brown-dwarf desert
• The Formation and Early Evolution of Low-mass Stars and Brown Dwarfs
• Search for brown-dwarf companions of stars
• SOPHIE velocimetry of Kepler transit candidates VII. A false-positive rate of 35% for Kepler close-in giant exoplanet candidates
• HAT-P-20b--HAT-P-23b: Four Massive Transiting Extrasolar Planets
• WASP-30b: a 61 Mjup brown dwarf transiting a V=12, F8 star
• SOPHIE+: First results of an octagonal-section fiber for high-precision radial velocity measurements
• On The Origins Of Eccentric Close-in Planets
• The EBLM Project I-Physical and orbital parameters, including spin-orbit angles, of two low-mass eclipsing binaries on opposite sides of the Brown Dwarf limit
• Transiting exoplanets from the CoRoT space mission. XV. CoRoT-15b: a brown dwarf transiting companion
• LHS6343C: A Transiting Field Brown Dwarf Discovered by the Kepler Mission
• A planet-sized transiting star around OGLE-TR-122 - Accurate mass and radius near the Hydrogen-burning limit
• SOPHIE velocimetry of Kepler transit candidates III. KOI-423b: an 18 Mjup transiting companion around an F7IV star
• Tidally induced brown dwarf and planet formation in circumstellar discs
• XX. CoRoT-20b: A very high density, high eccentricity transiting giant planet
• The SOPHIE search for northern extrasolar planets. IV. Massive companions in the planet-brown dwarf boundary
• The Posterior Distribution of sin(i) for Exoplanets with M_T sin(i) Determined from Radial Velocity Data

Cited by in corpus (48)

• Fundamental Parameters and Spectral Energy Distributions of Young and Field Age Objects with Masses Spanning the Stellar to Planetary Regime
• SOPHIE velocimetry of Kepler transit candidates XVII. The physical properties of giant exoplanets within 400 days of period
• BANYAN. VII. A New Population of Young Substellar Candidate Members of Nearby Moving Groups from the BASS Survey
• PASTIS: Bayesian extrasolar planet validation. I. General framework, models, and performance
• Kepler-413b: a slightly misaligned, Neptune-size transiting circumbinary planet
• Discovery and Validation of Kepler-452b: A 1.6-Re Super Earth Exoplanet in the Habitable Zone of a G2 Star
• Evidence of an Upper Bound on the Masses of Planets and its Implications for Giant Planet Formation
• Ab initio equations of state for hydrogen (H-REOS.3) and helium (He-REOS.3) and their implications for the interior of Brown Dwarfs
• Statistical Properties of Brown Dwarf Companions: Implications for Different Formation Mechanisms
• A Definition for Giant Planets Based on the Mass-Density Relationship
• Planets Transiting Non-Eclipsing Binaries
• SOPHIE velocimetry of Kepler transit candidates IX. KOI-415 b: a long-period, eccentric transiting brown dwarf to an evolved Sun
• Transiting exoplanets from the CoRoT space mission XXVIII. CoRoT-33b, an object in the brown dwarf desert with 2:3 commensurability with its host star
• The detection and characterisation of 54 massive companions with the SOPHIE spectrograph -- 7 new brown dwarfs and constraints on the BD desert
• Evaporation of dark matter from celestial bodies
• EPIC 219388192 b - an inhabitant of the brown dwarf desert in the Ruprecht 147 open cluster
• Spitzer and z' Secondary Eclipse Observations of the Highly Irradiated Transiting Brown Dwarf KELT-1b
• Two intermediate-mass transiting brown dwarfs from the TESS mission
• EPIC201702477b: A Long Period Transiting Brown Dwarf from K2
• Improved parameters of seven Kepler giant companions characterized with SOPHIE and HARPS-N
• First limits on the occurrence rate of short-period planets orbiting brown dwarfs
• The SOPHIE search for northern extrasolar planets IX. Populating the brown dwarf desert
• MOA-2007-BLG-197: Exploring the brown dwarf desert
• SOPHIE velocimetry of Kepler transit candidates XI. Kepler-412 system: probing the properties of a new inflated hot Jupiter
• KOI-200b and KOI-889b: two transiting exoplanets detected and characterized with Kepler, SOPHIE and HARPS-N
• Populating the brown dwarf and stellar boundary: Five stars with transiting companions near the hydrogen-burning mass limit
• TOI-811b and TOI-852b: New transiting brown dwarfs with similar masses and very different radii and ages from the TESS mission
• The Mass-Luminosity Relation in the L/T Transition: Individual Dynamical Masses for the New J-Band Flux Reversal Binary SDSSJ105213.51+442255.7AB
• TOI-503: The first known brown dwarf-Am star binary from the TESS mission
• OGLE-2015-BLG-1482L: the first isolated low-mass microlens in the Galactic bulge
• Uniform Forward-Modeling Analysis of Ultracool Dwarfs. II. Atmospheric Properties of 55 Late-T Dwarfs
• Colour-Magnitude Diagrams of Transiting Exoplanets. I - Systems with parallaxes
• New substellar discoveries from Kepler and K2: Is there a brown dwarf desert?
• Colour-magnitude diagrams of transiting Exoplanets - II. A larger sample from photometric distances
• Determining the true mass of radial-velocity exoplanets with Gaia: 9 planet candidates in the brown-dwarf/stellar regime and 27 confirmed planets
• Interplay of tidal evolution and stellar wind braking in the rotation of stars hosting massive close-in planets
• Three statistically validated K2 transiting warm Jupiter exoplanets confirmed as low-mass stars
• Characterizing the Cool KOIs. VII. Refined Physical Properties of the Transiting Brown Dwarf LHS 6343 C
• Individual, Model-Independent Masses of the Closest Known Brown Dwarf Binary to the Sun
• Three new brown dwarfs and a massive hot Jupiter revealed by TESS around early-type stars
• Improved radius determinations for the transiting brown dwarf population in the era of Gaia and TESS
• Characterization of the four new transiting planets KOI-188b, KOI-195b, KOI-192b, and KOI-830b
• TOI 694 b and TIC 220568520 b: Two Low-Mass Companions Near the Hydrogen Burning Mass Limit Orbiting Sun-like Stars
• CoRoT-22 b: a validated 4.9 RE exoplanet in 10-day orbit
• Multiplicity Boost Of Transit Signal Classifiers: Validation of 69 New Exoplanets Using The Multiplicity Boost of ExoMiner
• SOPHIE velocimetry of Kepler transit candidates. XIX. The transiting temperate giant planet KOI-3680b
• A New Brown Dwarf Orbiting an M star and An Investigation on the Eccentricity Distribution of Transiting Long-Period Brown Dwarfs
• Evidence of Radius Inflation Based on 50 Transiting Brown Dwarfs and Low-mass Stellar Companions