Asymmetry, Gap Opening and High Accretion Rate on DM Tau: A Hypothesis Based on Interaction of Magnetized Disk Wind with Planet

TL;DR

This study uses simulations with magnetized disk winds to explain the asymmetric gaps and high accretion rates in DM Tau, challenging traditional planet formation theories and suggesting a new mechanism for disk turbulence.

Contribution

It introduces a novel simulation approach incorporating magnetized disk winds to explain observed features in DM Tau, highlighting the role of magnetic effects in disk dynamics.

Findings

Simulations replicate observed gap and asymmetry in DM Tau

Magnetized disk winds can support medium-mass planets within gaps

High accretion rates may not require high turbulence levels

Abstract

Over two hundred protoplanetary disk systems have been resolved by ALMA, and the vast majority suggest the presence of planets. The dust gaps in transition disks are considered evidence of giant planets sculpting gas and dust under appropriate disk viscosity. However, the unusually high accretion rates in many T Tauri stars hosting transition disks challenge this theory. As the only disk currently observed with high turbulence, the high accretion rate ($\sim10^{-8.3}M_{\odot}/yr$) observed in DM Tau indicates the presence of strong turbulence may within the system. Considering the recent theoretical advancements in magnetized disk winds is challenging the traditional gap-opening theories and viscosity-driven accretion models, our study presents a pioneering simulation incorporating a simplified magnetized disk wind model to explain the observed features in DM Tau. Employing multi-fluid simulations with an embedded medium mass planet, we successfully replicate the gap formation and asymmetric structures evident in ALMA Band 6 and the recently JVLA 7 mm observations. Our results suggest that when magnetized disk wind dominate the accretion mode of the system, it's entirely possible for a planet with a medium mass to exist within the gap inside 20 au of DM Tau. This means that DM Tau may not be as turbulence as imagined. However, viscosity within the disk should also contribute a few turbulence to maintain disk stability.