Modest dust settling in the IRAS04302+2247 Class I protoplanetary disk

Abstract

We present new VLA observations, between 6.8mm and 66mm, of the edge-on Class~I disk IRAS04302+2247. Observations at 6.8mm and 9.2mm lead to the detection of thermal emission from the disk, while shallow observations at the other wavelengths are used to correct for emission from other processes. The disk radial brightness profile transitions from broadly extended in previous ALMA 0.9mm and 2.1mm observations to much more centrally brightened at 6.8mm and 9.2mm, which can be explained by optical depth effects. The radiative transfer modeling of the 0.9mm, 2.1mm, and 9.2mm data suggests that the grains are smaller than 1cm in the outer regions of the disk and allows us to obtain the first lower limit for the scale height of grains emitting at millimeter wavelengths in a protoplanetary disk. We find that the millimeter dust scale height is between 1au and 6au at a radius 100au from the central star, while the gas scale height is estimated to be about 7au, indicating a modest level of settling. The estimated dust height is intermediate between less evolved Class 0 sources, that are found to be vertically thick, and more evolved Class II sources, which show a significant level of settling. This suggests that we are witnessing an intermediate stage of dust settling.

Accepted for publication in the Astrophysical Journal

References in corpus (20)

• Array Programming with NumPy
• CASA, the Common Astronomy Software Applications for Radio Astronomy
• Particle Stirring in Turbulent Gas Disks: Including Orbital Oscillations
• Monte Carlo radiative transfer in protoplanetary disks
• Meridional flows in the disk around a young star
• The Radial Distribution of Dust Particles in the HL Tau Disk from ALMA and VLA Observations
• A highly settled disk around Oph 163131
• The ALMA view of the protostellar system HH212 - The wind, the cavity, and the disk
• ALMA Results of the Pseudodisk, Rotating disk, and Jet in Continuum and HCO+ in the Protostellar System HH 212
• The efficiency of dust trapping in ringed proto-planetary discs
• Constraining the Envelope Structure of L1527 IRS: Infrared Scattered Light Modeling
• Vertical Structure of the Transition Zone from Infalling Rotating Envelope to Disk in the Class 0 Protostar, IRAS04368+2557
• Searching for kinematic evidence of Keplerian disks around Class 0 protostars with CALYPSO
• Submillimeter Structure of the Disk of the Butterfly Star
• Substructure Formation in a Protostellar Disk of L1527 IRS
• Stratified Distribution of Organic Molecules at the Planet-Formation Scale in the HH 212 Disk Atmosphere
• Formation of dust clumps with sub-Jupiter mass and cold shadowed region in gravitationally unstable disk around Class 0/I protostar in L1527 IRS
• Millimeter Gap Contrast as a Probe for Turbulence Level in Protoplanetary Disks
• A millimeter-multiwavelength continuum study of VLA 1623 West
• Pebbles in an Embedded Protostellar Disk: The Case of CB26

Cited by in corpus (1)

• Empirical constraints on turbulence in proto-planetary discs