Radial Velocity Discovery of an Eccentric Jovian World Orbiting at 18 au

Abstract

Based on two decades of radial velocity (RV) observations using Keck/HIRES and McDonald/Tull, and more recent observations using the Automated Planet Finder, we found that the nearby star HR 5183 (HD 120066) hosts a 3$M_J$ minimum mass planet with an orbital period of $74_{-22}^{+43}$ years. The orbit is highly eccentric (e$\simeq$0.84), shuttling the planet from within the orbit of Jupiter to beyond the orbit of Neptune. Our careful survey design enabled high cadence observations before, during, and after the planet's periastron passage, yielding precise orbital parameter constraints. We searched for stellar or planetary companions that could have excited the planet's eccentricity, but found no candidates, potentially implying that the perturber was ejected from the system. We did identify a bound stellar companion more than 15,000 au from the primary, but reasoned that it is currently too widely separated to have an appreciable effect on HR 5183 b. Because HR 5183 b's wide orbit takes it more than 30 au (1") from its star, we also explored the potential of complimentary studies with direct imaging or stellar astrometry. We found that a Gaia detection is very likely, and that imaging at 10 $\mu$m is a promising avenue. This discovery highlights the value of long-baseline RV surveys for discovering and characterizing long-period, eccentric Jovian planets. This population may offer important insights into the dynamical evolution of planetary systems containing multiple massive planets.

arXiv comment23 pages, 12 figures. Accepted to AJ

References in corpus (69)

• emcee: The MCMC Hammer
• Gaia Data Release 2. Summary of the contents and survey properties
• Modules for Experiments in Stellar Astrophysics (MESA)
• Modules for Experiments in Stellar Astrophysics (MESA): Giant Planets, Oscillations, Rotation, and Massive Stars
• Modules for Experiments in Stellar Astrophysics (MESA): Binaries, Pulsations, and Explosions
• MESA Isochrones and Stellar Tracks (MIST). I: Solar-Scaled Models
• MESA Isochrones and Stellar Tracks (MIST) 0: Methods for the construction of stellar isochrones
• Direct Imaging of Multiple Planets Orbiting the Star HR 8799
• galpy: A Python Library for Galactic Dynamics
• The false positive rate of Kepler and the occurrence of planets
• Images of a fourth planet orbiting HR 8799
• The Keck Planet Search: Detectability and the Minimum Mass and Orbital Period Distribution of Extrasolar Planets
• Discovery of a planetary-mass companion within the gap of the transition disk around PDS 70
• The Occurrence and Mass Distribution of Close-in Super-Earths, Neptunes, and Jupiters
• A probable giant planet imaged in the Beta Pictoris disk
• Chromospheric CaII Emission in Nearby F, G, K, and M stars
• Discovery and spectroscopy of the young Jovian planet 51 Eri b with the Gemini Planet Imager
• RadVel: The Radial Velocity Modeling Toolkit
• The Discovery of a Planetary Companion to 16 Cygni B
• Chromospheric Activity and Jitter Measurements for 2630 Stars on the California Planet Search
• The Gemini Planet Imager Exoplanet Survey: Giant Planet and Brown Dwarf Demographics From 10-100 AU
• Ten New and Updated Multi-planet Systems, and a Survey of Exoplanetary Systems
• Imaging Extrasolar Giant Planets
• Friends of Hot Jupiters I: A Radial Velocity Search for Massive, Long-Period Companions to Close-In Gas Giant Planets
• LkCa 15: A Young Exoplanet Caught at Formation?
• Detection Limits from the McDonald Observatory Planet Search Program
• Limits on Planetary Companions from Doppler Surveys of Nearby Stars
• Asteroseismology and Gaia: Testing Scaling Relations Using 2200 Kepler Stars with TGAS Parallaxes
• The Exoplanet Mass-Ratio Function from the MOA-II Survey: Discovery of a Break and Likely Peak at a Neptune Mass
• Evidence for a Long-period Planet Orbiting Epsilon Eridani
• Improved Astrometry and Photometry for the Luyten Catalog. II. Faint Stars and the Revised Catalog
• A Plateau in the Planet Population Below Twice the Size of Earth
• Probing for Exoplanets Hiding in Dusty Debris Disks: Disk Imaging, Characterization, and Exploration with HST/STIS Multi-Roll Coronagraphy
• Discovery of a probable 4-5 Jupiter-mass exoplanet to HD 95086 by direct-imaging
• From binaries to multiples I: Data on F and G dwarfs within 67 pc of the Sun
• Discovery of a warm, dusty giant planet around HIP65426
• CARMENES input catalogue of M dwarfs. I. Low-resolution spectroscopy with CAFOS
• APF - The Lick Observatory Automated Planet Finder
• Statistics of Long Period Gas Giant Planets in Known Planetary Systems
• Four New Exoplanets and Hints of Additional Substellar Companions to Exoplanet Host Stars
• Dynamical Constraints on the HR 8799 Planets with GPI
• The Twenty-Five Year Lick Planet Search
• The Anglo-Australian Planet Search XXIV: The Frequency of Jupiter Analogs
• The giant planet orbiting the cataclysmic binary DP Leonis
• Searching for Planets in the Hyades II: Some Implications of Stellar Magnetic Activity
• On the Frequency of Jupiter Analogs
• The HARPS search for southern extrasolar planets. XXV. Four new planets in orbit around the moderatly active dwarfs HD 63765, HD 104067, HD 125595, and HIP 70849
• The planet search programme at the ESO CES and HARPS. IV. The search for Jupiter analogues around solar-like stars
• A Bayesian Periodogram Finds Evidence for Three Planets in 47 Ursae Majoris
• Astrometric Confirmation and Preliminary Orbital Parameters of the Young Exoplanet 51 Eridani b with the Gemini Planet Imager
• The CORALIE survey for southern extrasolar planets XVII. New and updated long period and massive planets
• The Anglo-Australian Planet Search. XXIII. Two New Jupiter Analogs
• A Model-Independent Mass and Moderate Eccentricity for $\beta$ Pic b
• Five Planets Transiting a Ninth Magnitude Star
• Three Super-Earths Orbiting HD 7924
• The SEEDS High Contrast Imaging Survey of Exoplanets around Young Stellar Objects
• Spectral and orbital characterisation of the directly imaged giant planet HIP 65426 b
• The CORALIE survey for southern extrasolar planets XVIII. Three new massive planets and two low mass brown dwarfs at separation larger than 5 AU
• The age structure of the Milky Way's halo
• Two New Long-Period Giant Planets from the McDonald Observatory Planet Search and Two Stars with Long-Period Radial Velocity Signals Related to Stellar Activity Cycles
• Constraints on the architecture of the HD 95086 planetary system with the Gemini Planet Imager
• KELT-21b: A Hot Jupiter Transiting the Rapidly-Rotating Metal-Poor Late-A Primary of a Likely Hierarchical Triple System
• The HARPS search for southern extra-solar planets XXXVI: Five new long-period giant planets and a system update
• The mass of planet GJ676A b from ground-based astrometry: A planetary system with two mature gas giants suitable for direct imaging
• Three Temperate Neptunes Orbiting Nearby Stars
• The Anglo-Australian Planet Search XXV: A Candidate Massive Saturn Analog Orbiting HD 30177
• The SOPHIE search for northern extrasolar planets VIII. Follow-up of ELODIE candidates: long-period brown-dwarf companions
• Bayesian evidence for two companions orbiting HIP 5158
• An improved catalog of halo wide binary candidates

Cited by in corpus (19)

• orbitize!: A Comprehensive Orbit-fitting Software Package for the High-contrast Imaging Community
• Cool Jupiters greatly outnumber their toasty siblings: Occurrence rates from the Anglo-Australian Planet Search
• The Kepler Giant Planet Search. I: A Decade of Kepler Planet-host Radial Velocities from W. M. Keck Observatory
• Constraining the Orbit and Mass of epsilon Eridani b with Radial Velocities, Hipparcos IAD-Gaia DR2 Astrometry, and Multi-epoch Vortex Coronagraphy Upper Limits
• Exoplanets with ELT-METIS I: Estimating the direct imaging exoplanet yield around stars within 6.5 parsecs
• The Masses of a Sample of Radial-Velocity Exoplanets with Astrometric Measurements
• In the Presence of a Wrecking Ball: Orbital Stability in the HR 5183 System
• Kepler-1656b's Extreme Eccentricity: Signature of a Gentle Giant
• Confirmation of the Long-Period Planet Orbiting Gliese 411 and the Detection of a New Planet Candidate
• Revisiting Orbital Evolution in HAT-P-2 b and Confirmation of HAT-P-2 c
• HD 83443c: A highly eccentric giant planet on a 22-year orbit
• The California Legacy Survey II. Occurrence of Giant Planets Beyond the Ice line
• An Edge-On Orbit for the Eccentric Long-Period Planet HR 5183 b
• A Wide Orbit Exoplanet OGLE-2012-BLG-0838Lb
• An HST/STIS View of Protoplanetary Disks in Upper Scorpius: Observations of Three Young M-Stars
• The California Legacy Survey I. A Catalog of 178 Planets from Precision Radial Velocity Monitoring of 719 Nearby Stars over Three Decades
• Asteroseismology of iota Draconis and Discovery of an Additional Long-Period Companion
• MOSES -- The MONET Star and Exoplanet Spectrograph
• Dynamical orbital evolution scenarios of the wide-orbit eccentric planet HR 5183b