TrES-4: A Transiting Hot Jupiter of Very Low Density

Abstract

We report the discovery of TrES-4, a hot Jupiter that transits the star GSC 02620-00648 every 3.55 days. From high-resolution spectroscopy of the star we estimate a stellar effective temperature of Teff = 6100 +/- 150 K, and from high-precision z and B photometry of the transit we constrain the ratio of the semi-major axis and the stellar radius to be a/R = 6.03 +/- 0.13. We compare these values to model stellar isochrones to constrain the stellar mass to be M* = 1.22 +/- 0.17 Msun. Based on this estimate and the photometric time series, we constrain the stellar radius to be R* = 1.738 +/- 0.092 Rsun and the planet radius to be Rp = 1.674 +/- 0.094 RJup. We model our radial-velocity data assuming a circular orbit and find a planetary mass of 0.84 +/- 0.10 MJup. Our radial-velocity observations rule out line-bisector variations that would indicate a specious detection resulting from a blend of an eclipsing binary system. TrES-4 has the largest radius and lowest density of any of the known transiting planets. It presents a challenge to current models of the physical structure of hot Jupiters, and indicates that the diversity of physical properties amongst the members of this class of exoplanets has yet to be fully explored.

References in corpus (32)

• Analytic Lightcurves for Planetary Transit Searches
• Evolutionary models for cool brown dwarfs and extrasolar giant planets. The case of HD 20945
• Planetary Radii across Five Orders of Magnitude in Mass and Stellar Insolation: Application to Transits
• Towards Better Age Estimates for Stellar Populations: The Y^2 Isochrones for Solar Mixture
• No planet for HD 166435
• The second US Naval Observatory CCD Astrograph Catalog (UCAC2)
• The effective temperature scale of FGK stars. II. Teff : color : [Fe/H] calibrations
• Roche lobe effects on the atmospheric loss of "Hot Jupiters"
• TrES-1: The Transiting Planet of a Bright K0V Star
• Evolution of "51Peg b-like" Planets
• Possible Solutions to the Radius Anomalies of Transiting Giant Planets
• Improving Stellar and Planetary Parameters of Transiting Planet Systems: The Case of TrES-2
• Prospects for the Characterization and Confirmation of Transiting Exoplanets via the Rossiter-McLaughlin Effect
• WASP-1b and WASP-2b: Two new transiting exoplanets detected with SuperWASP and SOPHIE
• On the Radii of Extrasolar Giant Planets
• HAT-P-1b: A Large-Radius, Low-Density Exoplanet Transiting one Member of a Stellar Binary
• Atmospheric Escape from Hot Jupiters
• Using Stellar Limb-Darkening to Refine the Properties of HD 209458b
• The CORALIE survey for southern extra-solar planets IX. A 1.3-day period brown dwarf disguised as a planet
• The Transit Light Curve (TLC) Project. I. Four Consecutive Transits of the Exoplanet XO-1b
• Heat transport in giant (exo)planets: a new perspective
• Accurate fundamental parameters for Lower Main Sequence Stars
• TrES-2: The First Transiting Planet in the Kepler Field
• A Theory for the Radius of the Transiting Giant Planet HD 209458b
• The Transit Light Curve Project. III. Tres Transits of TrES-1
• TrES-3: A Nearby, Massive, Transiting Hot Jupiter in a 31-Hour Orbit
• Spectroscopic binaries in a sample of ROSAT X-ray sources south of the Taurus molecular clouds
• The Challenge of Wide-Field Transit Surveys: The Case of GSC 01944-02289
• Precise Radius Estimates for the Exoplanets WASP-1b and WASP-2b
• The Transit Light Curve Project. VI. Three Transits of the Exoplanet TrES-2
• Testing blend scenarios for extrasolar transiting planet candidates. II. -- OGLE-TR-56
• A Keck/HIRES Doppler Search for Planets Orbiting Metal-Poor Dwarfs. I. Testing Giant Planet Formation and Migration Scenarios

Cited by in corpus (87)

• A Unified Theory for the Atmospheres of the Hot and Very Hot Jupiters: Two Classes of Irradiated Atmospheres
• Improved parameters for extrasolar transiting planets
• The 3.6-8.0 Micron Broadband Emission Spectrum of HD 209458b: Evidence for an Atmospheric Temperature Inversion
• Spin-orbit angle measurements for six southern transiting planets; New insights into the dynamical origins of hot Jupiters
• The GAPS Programme with HARPS-N@TNG XIV. Investigating giant planet migration history via improved eccentricity and mass determination for 231 transiting planets
• Friends of Hot Jupiters I: A Radial Velocity Search for Massive, Long-Period Companions to Close-In Gas Giant Planets
• The Transit Light Curve Project. IX. Evidence for a Smaller Radius of the Exoplanet XO-3b
• Can TiO Explain Thermal Inversions in the Upper Atmospheres of Irradiated Giant Planets?
• Line-profile tomography of exoplanet transits -- II. A gas-giant planet transiting a rapidly-rotating A5 star
• The Mass of KOI-94d and a Relation for Planet Radius, Mass, and Incident Flux
• The Broadband Infrared Emission Spectrum of the Exoplanet HD 189733b
• Homogeneous studies of transiting extrasolar planets. III. Additional planets and stellar models
• Theoretical Spectra and Light Curves of Close-in Extrasolar Giant Planets and Comparison with Data
• The coronal X-ray - age relation and its implications for the evaporation of exoplanets
• WASP-17b: an ultra-low density planet in a probable retrograde orbit
• Observational Evidence for Tidal Destruction of Exoplanets
• Absolute properties of the low-mass eclipsing binary CM Draconis
• Tidal Heating of Extra-Solar Planets
• Evidence of an Upper Bound on the Masses of Planets and its Implications for Giant Planet Formation
• Homogeneous studies of transiting extrasolar planets. V. New results for 38 planets
• HAT-P-12b: A Low-Density Sub-Saturn Mass Planet Transiting a Metal-Poor K Dwarf
• Two Classes of Hot Jupiters
• Binarity of Transit Host Stars - Implications on Planetary Parameters
• WASP-4b: a 12th-magnitude transiting hot-Jupiter in the Southern hemisphere
• Homogeneous studies of transiting extrasolar planets. II. Physical properties
• Double-blind test program for astrometric planet detection with Gaia
• HAT-P-39b--HAT-P-41b: Three Highly Inflated Transiting Hot Jupiters
• Extrasolar Giant Planets and X-ray Activity
• WASP-39b: a highly inflated Saturn-mass planet orbiting a late G-type star
• Calibration of Equilibrium Tide Theory for Extrasolar Planet Systems II
• A library of ATMO forward model transmission spectra for hot Jupiter exoplanets
• Detection of a Temperature Inversion in the Broadband Infrared Emission Spectrum of TrES-4
• Ground-based near-UV observations of 15 transiting exoplanets: Constraints on their atmospheres and no evidence for asymmetrical transits
• TESS Transit Timing of Hundreds of Hot Jupiters
• HAT-P-5b: A Jupiter-like hot Jupiter Transiting a Bright Star
• A New Spectroscopic and Photometric Analysis of the Transiting Planet Systems TrES-3 and TrES-4
• Extrasolar Planet Transits Observed at Kitt Peak National Observatory
• The Transit Light Curve project. XIV. Confirmation of Anomalous Radii for the Exoplanets TrES-4b, HAT-P-3b, and WASP-12b
• Analytic Description of the Rossiter-McLaughlin Effect for Transiting Exoplanets: Cross-Correlation Method and Comparison with Simulated Data
• Constraining Orbital Parameters Through Planetary Transit Monitoring
• WASP-5b: a dense, very-hot Jupiter transiting a 12th-mag Southern-hemisphere star
• WASP-35b, WASP-48b and WASP-51b: Two new planets and an independent discovery of HAT-P-30b
• Coupled Evolution with Tides of the Radius and Orbit of Transiting Giant Planets: General Results
• The Prograde Orbit of Exoplanet TrES-2b
• WASP-7: The brightest transiting-exoplanet system in the Southern hemisphere
• Empirical Constraints on Trojan Companions and Orbital Eccentricities in 25 Transiting Exoplanetary Systems
• ExoClock Project III: 450 new exoplanet ephemerides from ground and space observations
• HAT-P-4b: A metal-rich low-density transiting hot Jupiter
• Discovery and Atmospheric Characterization of Giant Planet Kepler-12b: An Inflated Radius Outlier
• The Broadband Infrared Emission Spectrum of the Exoplanet TrES-3
• Atmospheric Characterization of 5 Hot Jupiters with Wide Field Camera 3 on the Hubble Space Telescope
• HAT-P-65b and HAT-P-66b: Two Transiting Inflated Hot Jupiters and Observational Evidence for the Re-Inflation of Close-In Giant Planets
• Tidal Heating Models for the Radii of the Inflated Transiting Giant Planets WASP-4b, WASP-6b, WASP-12b, and TrES-4
• OGLE2-TR-L9: An extrasolar planet transiting a fast-rotating F3 star
• High-precision photometry by telescope defocussing. IV. Confirmation of the huge radius of WASP-17b
• The composition of transiting giant extrasolar planets
• WASP-31b: a low-density planet transiting a metal-poor, late-F-type dwarf star
• The low density transiting exoplanet WASP-15b
• The Frequency of Large Radius Hot and Very Hot Jupiters in omega Centauri
• WASP-22 b: A transiting "hot Jupiter" planet in a hierarchical triple system
• ExoClock project II: A large-scale integrated study with 180 updated exoplanet ephemerides
• High precision transit observations of the exoplanet WASP-13b with the RISE instrument
• Explorations into the Viability of Coupled Radius-Orbit Evolutionary Models for Inflated Planets
• Parameters and Predictions for the Long-Period Transiting Planet HD 17156b
• Independent confirmation and refined parameters of the hot Jupiter XO-5b
• Transiting exoplanets from the CoRoT space mission. XII. CoRoT-12b: a short-period low-density planet transiting a solar analog star
• Theoretical Radii of Extrasolar Giant Planets: the Cases of TrES-4, XO-3b, and HAT-P-1b
• Structure and evolution of the first CoRoT exoplanets: Probing the Brown Dwarf/Planet overlapping mass regime
• HAT-P-24b: An inflated hot-Jupiter on a 3.36d period transiting a hot, metal-poor star
• Colour-magnitude diagrams of transiting Exoplanets - II. A larger sample from photometric distances
• Heavy Element Enrichment of a Jupiter-mass Protoplanet as a Function of Orbital Location
• An iterative filter to reconstruct planetary transit signals in the presence of stellar variability
• Embryo impacts and gas giant mergers II: Diversity of Hot Jupiters' internal structure
• A SuperWASP search for additional transiting planets in 24 known systems
• XO-2b: a Prograde Planet with a Negligible Eccentricity, and an Additional Radial Velocity Variation
• The GAPS Programme with HARPS-N@TNG VI: The Curious Case of TrES-4b
• Featureless transmission spectra of 12 giant exoplanets observed by GTC/OSIRIS
• BOWIE-ALIGN: A JWST comparative survey of aligned vs misaligned hot Jupiters to test the dependence of atmospheric composition on migration history
• SuperWASP-N Extra-solar Planet Candidates from Fields 06hr < RA < 16hr
• Interpreting the yield of transit surveys: Are there groups in the known transiting planets population?
• Photometric Orbits of Extrasolar Planets
• An a priori investigation of astrophysical false positives in ground-based transiting planet surveys
• Quantization of Planetary Systems and its Dependency on Stellar Rotation
• Molecular formation along the atmospheric mass loss of HD 209458 b and similar Hot Jupiters
• Planetary Transits and Tidal Evolution
• Observational Tests of Planet Formation Models
• TOI-1438: A rare system with two short-period sub-Neptunes and a tentative long-period Jupiter-like planet orbiting a K0V star