Long lived dust rings around HD169142

TL;DR

This study uses 3D simulations and radiative transfer modeling to suggest that two giant planets in resonance can create and sustain the observed dust rings around HD169142, with observable signatures in ALMA data.

Contribution

It demonstrates that resonant giant planets can produce long-lived dust ring structures consistent with ALMA observations of HD169142.

Findings

Dust rings are long-lived in the presence of resonant giant planets.

Inner planet's position influences dust ring shape and observable signatures.

Gas mass accretion onto star and planets empties the inner disc region.

Abstract

Recent ALMA observations of the protoplanetary disc around HD~169142 reveal a peculiar structure made of concentric dusty rings: a main ring at $\sim$20 au, a triple system of rings at $\sim 55-75$ au in millimetric continuum emission and a perturbed gas surface density from the $^{12}$CO,$^{13}$CO and C$^{18}$O$(J=2-1)$ surface brightness profile. In this Letter, we perform three-dimensional numerical simulations and radiative transfer modeling exploring the possibility that two giant planets interacting with the disc and orbiting in resonant locking can be responsible for the origin of the observed dust inner rings structure. We find that in this configuration the dust structure is actually long lived while the gas mass of the disc is accreted onto the star and the giant planets, emptying the inner region. In addition, we also find that the innermost planet is located at the inner edge of the dust ring, and can accrete mass from the disc, generating a signature in the dust ring shape that can be observed in mm ALMA observations.