2021ApJ...915L..21A -
Astrophys. J., 915, L21-L21 (2021/July-1)
The architecture of multiplanet systems as a tracer of their formation mechanisms.
ARORA U. and HASEGAWA Y.
Abstract (from CDS):
Exoplanets observed by the Kepler telescope exhibit a bimodal, radius distribution, which is known as the radius gap. We explore an origin of the radius gap, focusing on multiplanet systems. Our simple theoretical argument predicts that type I planetary migration produces different configurations of protoplanets with different masses and such different configurations can result in two distinguishable populations of small-sized multiplanet systems. We then perform an observational analysis to verify this prediction. In the analysis, multiple Kolmogorov-Smirnov tests are applied to the observed systems, using the statistical measures that are devised to systematically characterize the properties of multiplanet systems. We find with 99.5% confidence that the observed, small-sized multiplanet systems are divided into two distinct populations. The distinction likely originates from different spatial distributions of protoplanets, which are determined by type I migration and subsequently trigger giant impact. We also show that these distinct populations are separated around the radius gap when the gas surface density of protoplanetary disks is ∼102 g cm–2 in the vicinity of the host stars. This work therefore emphasizes the importance of planetary migration and the inner disk properties.
Abstract Copyright:
© 2021. The American Astronomical Society. All rights reserved.
Journal keyword(s):
Planet formation - Planetary migration - Super Earths - Mini Neptunes - Protoplanetary disks - Exoplanet dynamics
Simbad objects:
1
Full paper
View the references in ADS
To bookmark this query, right click on this link: simbad:2021ApJ...915L..21A and select 'bookmark this link' or equivalent in the popup menu