Positive metallicity correlation for coreless giant planets

Abstract

Frequency of detected giant planets is observed to increase rapidly with metallicity of the host star. This is usually interpreted as evidence in support of the Core Accretion (CA) theory, which assembles giant planets as a result of formation of a massive solid core. A strong positive planet-metallicity correlation for giant planets formed in the framework of Gravitational disc Instability (GI) model is found here. The key novelty of this work is "pebble accretion" onto GI fragments which has been recently demonstrated to accelerate contraction of GI fragments. Driven closer to the star by the inward migration, only the fragments that accrete metals rapidly enough collapse and survive the otherwise imminent tidal disruption. The survival fraction of simulated planets correlates strongly with the metallicity of the host star, as observed.

submitted to MNRAS Letters (version addressing referee's comments)

References in corpus (23)

• Rapid growth of gas-giant cores by pebble accretion
• The Formation of a Star Cluster: Predicting the Properties of Stars and Brown Dwarfs
• The effect of gas drag on the growth of protoplanets -- Analytical expressions for the accretion of small bodies in laminar disks
• On the width and shape of gaps in protoplanetary disks
• Can giant planets form by direct gravitational instability?
• The Burst Mode of Protostellar Accretion
• Investigating fragmentation conditions in self-gravitating accretion discs
• Clumps in the Outer Disk by Disk Instability: Why They are Initially Gas Giants and the Legacy of Disruption
• Non-steady Accretion in Protostars
• Challenges in Forming Planets by Gravitational Instability: Disk Irradiation and Clump Migration, Accretion & Tidal Destructio
• Formation of planets by tidal downsizing of giant planet embryos
• Rapid inward migration of planets formed by gravitational instability
• Constraining the initial entropy of directly-detected exoplanets
• Towards a Population Synthesis Model of Objects formed by Self-Gravitating Disc Fragmentation and Tidal Downsizing
• Effects of Helium Phase Separation on the Evolution of Extrasolar Giant Planets
• Core Formation in Giant Gaseous Protoplanets
• Fu Ori outbursts and the planet-disc mass exchange
• A numerical simulation of a "super-Earth" core delivery from ~ 100 AU to ~ 8 AU
• The Effects of Metallicity, and Grain Growth and Settling on the Early Evolution of Gaseous Protoplanets
• Formation of terrestrial planet cores inside giant planet embryos
• The collapse of protoplanetary clumps formed through disc instability: 3D simulations of the pre-dissociation phase
• On the Evolution and Survival of Protoplanets Embedded in a Protoplanetary Disk
• Metal loading of giant gas planets

Cited by in corpus (14)

• Towards a population synthesis model of self-gravitating disc fragmentation and tidal downsizing II: The effect of fragment-fragment interactions
• The Correlation Between Metallicity and Debris Disk mass
• The LEECH Exoplanet Imaging Survey: Characterization of the Coldest Directly Imaged Exoplanet, GJ 504 b, and Evidence for Super-Stellar Metallicity
• Dawes Review. The tidal downsizing hypothesis of planet formation
• Disc fragmentation rarely forms planetary-mass objects
• Tidal Downsizing model. I. Numerical methods: saving giant planets from tidal disruptions
• Tidal Downsizing Model. III. Planets from sub-Earths to Brown Dwarfs: structure and metallicity preferences
• The Effect of Protoplanetary Disk Cooling Times on the Formation of Gas Giant Planets by Gravitational Instability
• Chemical analysis of early-type stars with planets
• Tidal Downsizing Model. IV. Destructive feedback in planets
• On the origin of wide-orbit ALMA planets: giant protoplanets disrupted by their cores
• The paradox of youth for ALMA planet candidates
• Planets, debris and their host metallicity correlations
• Intermediate-mass stars and the origin of the gas-giant planet-metallicity correlation