Earths in Other Solar Systems N-body simulations: the Role of Orbital Damping in Reproducing the Kepler Planetary Systems

Abstract

The population of exoplanetary systems detected by Kepler provides opportunities to refine our understanding of planet formation. Unraveling the conditions needed to produce the observed exoplanets will sallow us to make informed predictions as to where habitable worlds exist within the galaxy. In this paper, we examine using N-body simulations how the properties of planetary systems are determined during the final stages of assembly. While accretion is a chaotic process, trends in the ensemble properties of planetary systems provide a memory of the initial distribution of solid mass around a star prior to accretion. We also use EPOS, the Exoplanet Population Observation Simulator, to account for detection biases and show that different accretion scenarios can be distinguished from observations of the Kepler systems. We show that the period of the innermost planet, the ratio of orbital periods of adjacent planets, and masses of the planets are determined by the total mass and radial distribution of embryos and planetesimals at the beginning of accretion. In general, some amount of orbital damping, either via planetesimals or gas, during accretion is needed to match the whole population of exoplanets. Surprisingly, all simulated planetary systems have planets that are similar in size, showing that the "peas in a pod" pattern can be consistent with both a giant impact scenario and a planet migration scenario. The inclusion of material at distances larger than what Kepler observes has a profound impact on the observed planetary architectures, and thus on the formation and delivery of volatiles to possible habitable worlds.

Resubmitted to ApJ. Planet formation models available online at http://eos-nexus.org/genesis-database/

References in corpus (13)

• The NumPy array: a structure for efficient numerical computation
• A stellar-mass-dependent drop in planet occurrence rates
• The structure of protoplanetary discs around evolving young stars
• Water Delivery and Giant Impacts in the 'Grand Tack' Scenario
• Exploring Exoplanet Populations with NASA's Kepler Mission
• Three-dimensional simulations of multiple protoplanets embedded in a protostellar disc
• A decreased probability of habitable planet formation around low-mass stars
• On the formation of planetary systems via oligarchic growth in thermally evolving viscous discs
• Volatile Delivery to Planets from Water-rich Planetesimals around Low Mass Stars
• Accounting for Incompleteness due to Transit Multiplicity in Kepler Planet Occurrence Rates
• Forming Diverse Super-Earth Systems in Situ
• The Effect of Planets Beyond the Ice Line on the Accretion of Volatiles by Habitable-Zone Rocky Planets
• Formation of short-period planets by disk migration

Cited by in corpus (15)

• The New Generation Planetary Population Synthesis (NGPPS). I. Bern global model of planet formation and evolution, model tests, and emerging planetary systems
• Large Area X-ray Proportional Counter (LAXPC) in Orbit Performance : Calibration, background, analysis software
• The New Generation Planetary Population Synthesis (NGPPS). V. Predetermination of planet types in global core accretion models
• The New Generation Planetary Population Synthesis (NGPPS). VI. Introducing KOBE: Kepler Observes Bern Exoplanets. Theoretical perspectives on the architecture of planetary systems: Peas in a pod
• A framework for the architecture of exoplanetary systems. I. Four classes of planetary system architecture
• The Demographics of Kepler's Earths and super-Earths into the Habitable Zone
• A framework for the architecture of exoplanetary systems. II. Nature versus nurture: Emergent formation pathways of architecture classes
• How Close are Compact Multi-Planet Systems to the Stability Limit?
• Pterodactyls: A Tool to Uniformly Search and Vet for Young Transiting Planets In TESS Primary Mission Photometry
• Effects of Planetesimal Scattering: Explaining the Observed Offsets from Period Ratios 3:2 and 2:1
• Migration traps as the root cause of the Kepler dichotomy
• Quantifying the Similarity of Planetary System Architectures
• Forming rocky exoplanets around K-dwarf stars
• The architecture of multi-planet systems as a tracer of their formation mechanisms
• Radius and mass distribution of ultra-short period planets