Measuring turbulent motion in planet-forming disks with ALMA: A detection around DM Tau and non-detections around MWC 480 and V4046 Sgr

Abstract

Turbulence is a crucial factor in many models of planet formation, but it has only been directly constrained among a small number of planet forming disks. Building on the upper limits on turbulence placed in disks around HD 163296 and TW Hya, we present ALMA CO J=2-1 line observations at $\sim 0.3"$ (20-50 au) resolution and 80 ms${}^{-1}$ channel spacing of the disks around DM Tau, MWC 480, and V4046 Sgr. Using parametric models of disk structure, we robustly detect non-thermal gas motions around DM Tau of between 0.25 c${}_s$ and 0.33 c${}_s$, with the range dominated by systematic effects, making this one of the only systems with directly measured non-zero turbulence. Using the same methodology, we place stringent upper limits on the non-thermal gas motion around MWC 480 ($<$0.08c${}_s$) and V4046 Sgr ($<$0.12 c${}_s$). The preponderance of upper limits in this small sample, and the modest turbulence levels consistent with dust studies, suggest that weak turbulence ($\alpha \lesssim 10^{-3}$) may be a common, albeit not universal, feature of planet-forming disks. We explore the particular physical conditions around DM Tau that could lead this system to be more turbulent than the others.

21 pages, 10 figures, accepted to ApJ

References in corpus (36)

• Gas- and dust evolution in protoplanetary disks
• Particle Stirring in Turbulent Gas Disks: Including Orbital Oscillations
• Closed-form expressions for particle relative velocities induced by turbulence
• On the age of the $\beta$ Pictoris moving group
• A Three-Dimensional View of Turbulence: Constraints on Turbulent Motions in the HD 163296 Protoplanetary Disk using DCO${}^{+}$
• Three radial gaps in the disk of TW Hydrae imaged with SPHERE
• Direct mapping of the temperature and velocity gradients in discs. Imaging the vertical CO snow line around IM Lupi
• Multiple Disk Gaps and Rings Generated by a Single Super-Earth
• The Coupled Physical Structure of Gas and Dust in the IM Lup Protoplanetary Disk
• Mass measurements in protoplanetary disks from hydrogen deuteride
• Millimeter imaging of HD 163296: probing the disk structure and kinematics
• Magnetic Flux Concentration and Zonal Flows in Magnetorotational Instability Turbulence
• Reprocessing of Ices in Turbulent Protoplanetary Disks: Carbon and Nitrogen Chemistry
• Tracing Slow Winds from T Tauri Stars via Low Velocity Forbidden Line Emission
• Temperaments of young stars: Rapid mass-accretion rate changes in T Tauri and Herbig Ae stars
• Radiation Hydrodynamical Turbulence In Protoplanetary Disks: Numerical Models and Observational Constraints
• Dust unveils the formation of a mini-Neptune planet in a protoplanetary ring
• An ALMA survey of DCN/H${}^{13}$CN and DCO${}^{+}$/H${}^{13}$CO${}^{+}$ in protoplanetary disks
• Protoplanetary disc `isochrones' and the evolution of discs in the $\dot{M}-M_{\mathrm{d}}$ plane
• Constraints from Dust Mass and Mass Accretion Rate Measurements on Angular Momentum Transport in Protoplanetary Disks
• Protoplanetary Disks as (Possibly) Viscous Disks
• The masses of young stars: CN as a probe of dynamical masses
• Dust Coagulation and Settling in Layered Protoplanetary Disks
• Chemistry in Disks. IX. Observations and modeling of HCO+ and DCO+ in DM Tau
• Investigating the inner discs of Herbig Ae/Be stars with CO bandhead and Br Gamma emission
• Spontaneous ring formation in wind-emitting accretion discs
• Stringent limits on the magnetic field strength in the disc of TW Hya: ALMA observations of CN polarisation
• Midplane temperature and outer edge of the protoplanetary disk around HD 163296
• CO emission tracing a warp or radial flow within $\lesssim$ 100 au in the HD 100546 protoplanetary disk
• New Constraints From Dust Lines On The Surface Densities Of Protoplanetary Disks
• Variable H${}^{13}$CO${}^{+}$ Emission in the IM Lup Disk: X-ray Driven Time-Dependent Chemistry?
• Jets, accretion, coronae and all that: The enigmatic X-rays from the Herbig star HD 163296
• A Surface Density Perturbation in the TW Hydrae Disk at 95 au Traced by Molecular Emission
• Radial variations in grain sizes and dust scale heights in the protoplanetary disk around HD 163296 revealed by ALMA polarization observation
• Gravito-Turbulent Disks in 3D: Turbulent Velocities vs. Depth
• Turbulent-diffusion Mediated CO Depletion in Weakly Turbulent Protoplanetary disks

Cited by in corpus (3)

• A dusty origin for the correlation between protoplanetary disc accretion rates and dust masses
• On dust evolution in planet-forming discs in binary systems. I -- Theoretical and numerical modelling: radial drift is faster in binary discs
• On the cavity size in circumbinary discs