Bifurcated Evolutionary Pathways in Multi-planet Systems Driven by Misaligned Protoplanetary Disks

Abstract

Stellar obliquities, or spin-orbit angles, prevalent in exoplanet systems, can impose important constraints on their formation and evolution histories. Recent studies suggest that primordial misalignments between protoplanetary disks and stellar spin axes may significantly contribute to these obliquities, as those frequently observed in systems hosting hot Jupiters. In this study, we demonstrate that misaligned protoplanetary disks combined with stellar oblateness drive complex dynamical evolution in planetary systems during their disk dispersal stages. Specifically, we identify bifurcated evolutionary pathways in multi-planet systems: systems with low star-disk misalignment angles (${\psi }_{\star 0}$) undergo smooth, adiabatic evolution, producing nearly coplanar, low-obliquity configurations; in contrast, systems with high misalignment angles typically experience an abrupt, non-adiabatic transition, leading to large-amplitude libration of mutual planetary inclinations and then triggering chaotic eccentricity excitation. This libration and eccentricity excitation process can propagate inward-outward in compact multi-planet systems, forming an excitation chain that can destabilize the entire system. The non-adiabatic transition arises from the dynamical bifurcation-induced effect, which occurs during disk dissipation when ${\psi }_{\star 0}\gtrsim 44.6^{\circ }$ (for one-planet systems). Our framework predicts that surviving typical compact multi-planet systems originating from misaligned disks evolve toward coplanar, low-obliquity configurations, consistent with observations of Kepler multi-planet systems. These results advance our understanding of planetary dynamics in misaligned disks and their evolutionary outcomes.

16 pages, 11 figures, submitted to The Astrophysical Journal Letters (ApJL)

References in corpus (39)

• Shrinking binary and planetary orbits by Kozai cycles with tidal friction
• Hot Stars with Hot Jupiters Have High Obliquities
• Obliquities of Hot Jupiter host stars: Evidence for tidal interactions and primordial misalignments
• Origins of Hot Jupiters
• Planetary Candidates Observed by Kepler. VIII. A Fully Automated Catalog With Measured Completeness and Reliability Based on Data Release 25
• The California-Kepler Survey V. Peas in a Pod: Planets in a Kepler Multi-planet System are Similar in Size and Regularly Spaced
• Evidence of Possible Spin-Orbit Misalignment Along the Line of Sight in Transiting Exoplanet Systems
• In Situ Formation and Dynamical Evolution of Hot Jupiter Systems
• Post-Oligarchic Evolution of Protoplanetary Embryos and the Stability of Planetary Systems
• Kepler Multi-Planet Systems Exhibit Unexpected Intra-system Uniformity in Mass and Radius
• On the evolution of eccentric and inclined protoplanets embedded in protoplanetary disks
• Three Body Resonance Overlap in Closely Spaced Multiple Planet Systems
• The In Situ Formation of Giant Planets at Short Orbital Periods
• Architectures of Exoplanetary Systems. I: A Clustered Forward Model for Exoplanetary Systems around Kepler's FGK Stars
• Magnetic and Gravitational Disk-Star Interactions: An Interdependence of PMS Stellar Rotation Rates and Spin-Orbit Misalignments
• A Preponderance of Perpendicular Planets
• A circumbinary protoplanetary disc in a polar configuration
• Gauss's method for secular dynamics, softened
• Spin-orbit Misalignment as a Driver of the Kepler Dichotomy
• A disk-driven resonance as the origin of high inclinations of close-in planets
• Larger mutual inclinations for the shortest-period planets
• A backward-spinning star with two coplanar planets
• Evidence for Hidden Nearby Companions to Hot Jupiters
• Angular momentum evolution of young low-mass stars and brown dwarfs: observations and theory
• Planet Formation in Disks with Inclined Binary Companions: Can Primordial Spin-Orbit Misalignment be Produced?
• Why do Earth satellites stay up?
• The Secular Evolution of the Primordial Kuiper Belt
• Excitation of Planetary Obliquities Through Planet-Disk Interactions
• Star-disc (mis-)alignment in Rho Oph and Upper Sco: insights from spatially resolved disc systems with K2 rotation periods
• High-Eccentricity Migration with Disk-Induced Spin-Orbit Misalignment: a Preference for Perpendicular Hot Jupiters
• A giant planet transiting a 3-Myr protostar with a misaligned disk
• Dynamics of Colombo's Top: Generating Exoplanet Obliquities from Planet-Disk Interactions
• Statistical Trends in the Obliquity Distribution of Exoplanet Systems
• Stellar Oblateness versus Distant Giants in Exciting Kepler Planet Mutual Inclinations
• Exterior Companions to Hot Jupiters Orbiting Cool Stars are Coplanar
• Potential-density pairs for a family of finite disks
• The chaotic history of the retrograde multi-planet system in K2-290A driven by distant stars
• The gravitational force and potential of the finite Mestel disk
• Sculpting of Exoplanetary Systems Driven by a Misaligned Disk and Stellar Oblateness: Origin of Perpendicular Orbits in HD 3167