Origins of Hot Jupiters from the Stellar Obliquity Distribution

Abstract

The obliquity of a star, or the angle between its spin axis and the average orbit normal of its companion planets, provides a unique constraint on that system's evolutionary history. Unlike the Solar System, where the Sun's equator is nearly aligned with its companion planets, many hot Jupiter systems have been discovered with large spin-orbit misalignments, hosting planets on polar or retrograde orbits. We demonstrate that, in contrast to stars harboring hot Jupiters on circular orbits, those with eccentric companions follow no population-wide obliquity trend with stellar temperature. This finding can be naturally explained through a combination of high-eccentricity migration and tidal damping. Furthermore, we show that the joint obliquity and eccentricity distributions observed today are consistent with the outcomes of high-eccentricity migration, with no strict requirement to invoke the other hot Jupiter formation mechanisms of disk migration or in-situ formation. At a population-wide level, high-eccentricity migration can consistently shape the dynamical evolution of hot Jupiter systems.

10 pages, 5 figures, accepted to ApJL

References in corpus (14)

• Array Programming with NumPy
• The NumPy array: a structure for efficient numerical computation
• Tidal dissipation in stars and giant planets
• Steady-state planet migration by the Kozai-Lidov mechanism in stellar binaries
• Kepler Multi-Planet Systems Exhibit Unexpected Intra-system Uniformity in Mass and Radius
• Friends of Hot Jupiters II: No Correspondence Between Hot-Jupiter Spin-Orbit Misalignment and the Incidence of Directly Imaged Stellar Companions
• On the tidal origin of hot Jupiter stellar obliquity trends
• Chaotic Tides in Migrating Gas Giants: Forming Hot and Transient Warm Jupiters via High-Eccentricity Migration
• New prospects for observing and cataloguing exoplanets in well detached binaries
• Formation of Hot Jupiters through Secular Chaos and Dynamical Tides
• Moderately Eccentric Warm Jupiters from Secular Interactions with Exterior Companions
• The Aligned Orbit of the Eccentric Warm Jupiter K2-232b
• Revisiting migration in a disc cavity to explain the high eccentricities of warm Jupiters
• Stellar Obliquities in Long-period Exoplanet Systems (SOLES) I: The Spin-Orbit Alignment of K2-140 b

Cited by in corpus (34)

• Stellar obliquities in exoplanetary systems
• The Upper Edge of the Neptune Desert Is Stable Against Photoevaporation
• Evidence for Hidden Nearby Companions to Hot Jupiters
• A Tendency Toward Alignment in Single-Star Warm Jupiter Systems
• Obliquities of Exoplanet Host Stars: 19 New and Updated Measurements, and Trends in the Sample of 205 Measurements
• High-Eccentricity Migration with Disk-Induced Spin-Orbit Misalignment: a Preference for Perpendicular Hot Jupiters
• TOI-3984 A b and TOI-5293 A b: two temperate gas giants transiting mid-M dwarfs in wide binary systems
• Three long period transiting giant planets from TESS
• The Orbital Architecture of Qatar-6: A Fully Aligned 3-Body System?
• TOI-1859b: A 64-Day Warm Jupiter on an Eccentric and Misaligned Orbit
• HIP 33609 b: An Eccentric Brown Dwarf Transiting a V=7.3 Rapidly Rotating B-Star
• The Spin-Orbit Misalignment of TOI-1842b: The First Measurement of the Rossiter-McLaughlin Effect for a Warm Sub-Saturn around a Massive Star
• The GAPS Programme at TNG: XXXVI. Measurement of the Rossiter-McLaughlin effect and revising the physical and orbital parameters of the HAT-P-15, HAT-P-17, HAT-P-21, HAT-P-26, HAT-P-29 eccentric planetary systems
• The Spin-Orbit Alignment of 8 Warm Gas Giant Systems
• The PFS view of TOI-677 b: A spin-orbit aligned warm Jupiter in a dynamically hot system
• The OATMEAL Survey. I. Low Stellar Obliquity in the Transiting Brown Dwarf System GPX-1
• A third star in the HAT-P-7 system, and a new dynamical pathway to misaligned hot Jupiters
• A High-Eccentricity Warm Jupiter Orbiting TOI-4127
• TESS Giants Transiting Giants. VI. Newly Discovered Hot Jupiters Provide Evidence for Efficient Obliquity Damping after the Main Sequence
• Confirmation and characterisation of three giant planets detected by TESS from the FIES/NOT and Tull/McDonald spectrographs
• A close outer companion to the ultra-hot Jupiter TOI-2109 b?
• The First Spin-Orbit Obliquity of an M dwarf/brown dwarf System: An eccentric and aligned TOI-2119 b
• The Orbit of Warm Jupiter WASP-106 b is aligned with its Star
• Evidence for Primordial Alignment II: Insights from Stellar Obliquity Measurements for Hot Jupiters in Compact Multiplanet Systems
• GEMS JWST: Transmission spectroscopy of TOI-5205b reveals significant stellar contamination and a metal-poor atmosphere
• Tidal synchronization trapping in stars and planets with convective envelopes
• Forming short period sub-stellar companions in 47 Tucanae -- II. Analytic expressions for the orbital evolution of planets in dense environments
• Small and Close-In Planets are Uncommon Around A-type Stars
• The OATMEAL Survey. III. An Aligned Transiting Warm Brown Dwarf and Evidence for Quiescent Brown Dwarf Migration
• The Formation of Double Hot Jupiter Systems through von Zeipel-Lidov-Kozai Migration
• TOI-1259Ab: A Warm Jupiter Orbiting a K-dwarf White-Dwarf Binary is on a Well-aligned Orbit
• Evidence for the Late Arrival of Hot Jupiters in Systems with High Host-star Obliquities
• A Homogeneous Catalog of Rossiter-McLaughlin Systems: Distinct $e$-$\lambda$ Trends in Three Gas-Giant Mass Regimes
• The EBLM Project XVIII. 3D Obliquities of Five Low-Mass Eclipsing Binaries