eDisk Modeling of a Protostellar Disk: Viscous Accretion Heating and Dust and Gas Radii

Shigehisa Takakuwa, Kazuya Saigo, Miyu Kido, Nagayoshi Ohashi, John J. Tobin, Jes Kristian Jorgensen, eDisk Team

We will show our models to reproduce images of protostellar disks observed with our ALMA Large Program; Early Planet Formation in Embedded Disks (eDisk). eDisk has observed 17 protostellar sources plus two sources from the archive at a spatial resolution of ~5 au in the 1.3-mm dust-continuum emission, C18O (2-1), and the other band 6 lines. The 1.3-mm images of eDisk targets show inclined bright dusty disks associated with the protostars with a typical radius of 50-100 au. Several of those disks as seen in the 1.3-mm dust-continuum emission exhibit a high peak brightness temperature of >150 K, and asymmetric intensity distributions along the minor axes. Our radiative transfer modeling of the dust emission has found that a dusty disk passively heating by the central protostar cannot reproduce the observed bright dust-continuum emission. Internal heating in the dusty disk, such as viscous accretion heating, is likely required to reproduce the observed high brightness temperature of the 1.3-mm emission. The observed asymmetric intensity distributions along the minor axes can be interpreted by the dust flaring coupled with the optically thick 1.3-mm emission. Furthermore, our modeling has revealed that a larger radius of the molecular gas than that of the dust is required to reproduce both the dust and C18O distribution. We will summarize these results in our poster.

[Poster PDF File]