Formation of planetary cores at Type I migration traps

TL;DR

This paper investigates how particle trapping at pressure maxima in protoplanetary disks can facilitate the rapid formation of large planetary cores, potentially reaching 10 Earth masses within 1 million years.

Contribution

It demonstrates that pressure traps effectively promote the formation of large planetary embryos, advancing understanding of planet formation mechanisms.

Findings

Particle trapping leads to rapid planetesimal growth.

Large planetary cores up to 10 Earth masses can form within 1 Myr.

Pressure maxima are crucial sites for planet formation.

Abstract

One of the longstanding unsolved problems of planet formation is how solid bodies of a few decimeters in size can "stick" to form large planetesimals. This is known as the "meter size barrier". In recent years it has become increasingly clear that some form of "particle trapping" must have played a role in overcoming the meter size barrier. Particles can be trapped in long-lived local pressure maxima, such as those in anticyclonic vortices, zonal flows or those believed to occur near ice lines or at dead zone boundaries. Such pressure traps are the ideal sites for the formation of planetesimals and small planetary embryos. Moreover, they likely produce large quantities of such bodies in a small region, making it likely that subsequent N-body evolution may lead to even larger planetary embryos. The goal of this Letter is to show that this indeed happens, and to study how efficient it is. In particular, we wish to find out if rocky/icy bodies as large as 10 M_earth can form within 1 Myr, since such bodies are the precursors of gas giant planets in the core accretion scenario.