J/ApJ/786/33 Simulations of the late stage of planet formation (Quintana+, 2014)
The effect of planets beyond the ice line on the accretion of volatiles
by habitable-zone rocky planets.
Quintana E.V., Lissauer J.J.
<Astrophys. J., 786, 33 (2014)>
=2014ApJ...786...33Q 2014ApJ...786...33Q (SIMBAD/NED BibCode)
ADC_Keywords: Planets ; Models, evolutionary ; Stars, double and multiple
Keywords: astrobiology - planets and satellites: composition -
planets and satellites: dynamical evolution and stability -
planets and satellites: formation -
planets and satellites: terrestrial planets -
Abstract:
Models of planet formation have shown that giant planets have a large
impact on the number, masses, and orbits of terrestrial planets that
form. In addition, they play an important role in delivering volatiles
from material that formed exterior to the snow line (the region in the
disk beyond which water ice can condense) to the inner region of the
disk where terrestrial planets can maintain liquid water on their
surfaces. We present simulations of the late stages of terrestrial
planet formation from a disk of protoplanets around a solar-type star
and we include a massive planet (from 1 M{earth} to 1 MJ) in
Jupiter's orbit at ∼5.2 AU in all but one set of simulations. Two
initial disk models are examined with the same mass distribution and
total initial water content, but with different distributions of water
content. We compare the accretion rates and final water mass fraction
of the planets that form. Remarkably, all of the planets that formed
in our simulations without giant planets were water-rich, showing that
giant planet companions are not required to deliver volatiles to
terrestrial planets in the habitable zone. In contrast, an outer
planet at least several times the mass of Earth may be needed to clear
distant regions of debris truncating the epoch of frequent large
impacts. Observations of exoplanets from radial velocity surveys
suggest that outer Jupiter-like planets may be scarce, therefore, the
results presented here suggest that there may be more habitable
planets residing in our galaxy than previously thought.
Description:
Chambers (2001Icar..152..205C 2001Icar..152..205C) found that numerical simulations of the
final phases of terrestrial planet growth, which began with a bimodal mass
distribution consisting of many Mars-sized embryos embedded in a disk of
Moon-sized planetesimals, yielded configurations similar to the inner solar
system in many respects. Our simulations begin at this epoch and we follow
the evolution of embryos and planetesimals (with a 1:10 mass ratio) as
they collide and form into terrestrial planets. Outer planets, if included,
are assumed to have already formed. Our model begins with a total disk
mass of 4.85 M{earth} and is composed of 26 embryos, each with an initial
mass of 0.0933 M{earth} (2.8x10-7 M{earth}) and 260 planetesimals of
mass 0.00933 M{earth} (2.8x10-8 M{earth}). All bodies are assumed to
have a density of 3 g/cm3.
File Summary:
--------------------------------------------------------------------------------
FileName Lrecl Records Explanations
--------------------------------------------------------------------------------
ReadMe 80 . This file
table3.dat 35 6407 Final Planets and the Embryos/Planetesimals
Each Accreted
--------------------------------------------------------------------------------
See also:
J/ApJ/770/90 : Candidate planets in the habitable zones (Gaidos, 2013)
J/AJ/151/59 : Catalog of Earth-Like Exoplanet Survey Targets (Chandler+, 2016)
Byte-by-byte Description of file: table3.dat
--------------------------------------------------------------------------------
Bytes Format Units Label Explanations
--------------------------------------------------------------------------------
1- 8 A8 --- Run Simulation run identifier
10- 14 A5 --- Planet Final planet identifier (EMNN; PLNNN)
16- 20 A5 --- Comp Embryo or planetesimal indentifier (EMNN; PLNNN)
22- 27 F6.4 Mgeo Mass Mass
29- 35 F7.4 AU a Semi-major axis
--------------------------------------------------------------------------------
History:
From electronic version of the journal
(End) Prepared by [AAS], Tiphaine Pouvreau [CDS] 20-Jul-2017