Pulsed Disc Accretion Driven by Hot Jupiters

TL;DR

This study uses 2D hydrodynamical simulations to show that hot Jupiters can induce pulsed accretion at the inner edge of protoplanetary discs, explaining observed luminosity variability in systems like CI Tau.

Contribution

It demonstrates that massive, eccentric hot Jupiters can cause pulsed accretion, providing a new explanation for luminosity variability in young stellar systems.

Findings

Massive eccentric planets drive pulsed accretion at the disc edge.

Accretion variability amplitude increases with planet mass and eccentricity.

Simulation results can explain observed luminosity variations in CI Tau.

Abstract

We present 2D hydrodynamical simulations of hot Jupiters orbiting near the inner edge of protoplanetary discs. We systemically explore how the accretion rate at the inner disc edge is regulated by a giant planet of different mass, orbital separation and eccentricity. We find that a massive (with planet-to-star mass ratio $\gtrsim 0.003$) eccentric ($e_p\gtrsim 0.1$) planet drives a pulsed accretion at the inner edge of the disc, modulated at one or two times the planet's orbital frequency. The amplitude of accretion variability generally increases with the planet mass and eccentricity, although some non-monotonic dependences are also possible. Applying our simulation results to the T Tauri system CI Tau, where a young hot Jupiter candidate has been detected, we show that the observed luminosity variability in this system can be explained by pulsed accretion driven by an eccentric giant planet.