Evidence for Growth of Eccentricity and Mass Clearing in a Disc Interior to a Planet

TL;DR

This paper demonstrates through computational modeling that the eccentricity of a protoplanetary disc can grow significantly due to the evolving surface density, potentially explaining large inner holes in observed discs.

Contribution

It introduces a new mechanism where disc eccentricity growth is driven by the evolving surface density and resonance balance, affecting disc clearing.

Findings

Inner disc eccentricity can reach 0.3

Eccentricity growth can lead to disc material accretion onto the star

Provides an alternative explanation for large disc holes

Abstract

We present computational results showing eccentricity growth in the inner portions of a protoplanetary disc. We attribute this to the evolving surface density of the disc. The planet creates a gap, which adjusts the balance between the 3:1 (eccentricity exciting) and 2:1 (eccentricity damping) resonances. The eccentricity of the inner disc can rise as high as 0.3, which is sufficient to cause it to be accreted onto the star. This offers an alternative mechanism for producing the large holes observed in the discs of CoKu Tau/4, GM Aur and DM Tau.