Name: Mario Juric
Institution: Princeton University
University of Washington
Astrolunch
Title: Dynamical evolution at work: orbital properties of extrasolar
planets
Abstract:
There are over 150 extrasolar planetary systems known today, having
planets with a wide variety of masses, orbit eccentricities,
inclinations and semimajor axes. Their properties result from a
combination of the early formation process, lasting 1 Myr or less
(including interactions with the protoplanetary disk such as migration),
and the long-term (~Gyr timescale) dynamical evolution that follows
after planet formation is complete and the disk has been cleared out.
The relative role of these two stages in shaping observed planetary
systems is not yet known.
In this work, we investigate the long-term evolution of ensembles of
planetary systems, on 10 Myr to 3 Gyr timescales. As there is no global
stability criterion for few-body problems, to find and study stable
systems we turn to numerical integrations using an improved version of
the hybrid symplectic algorithm described in Chambers (1999), and with
initial conditions set by Monte Carlo simulations of a large number of
random planetary systems. We successfully construct ensembles of systems
that reproduce the observed eccentricity distribution, and find it to be
largely insensitive to details of initial conditions. We further find a
correlation between median eccentricity and the number of planets in a
system, which will be tested in observations as more multi-planet
systems become known.
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