Early Planet Formation in Embedded Disks (eDisk): Limited Dust Settling in the Edge-on Class I Protostar IRAS 04302+2247

Zhe-Yu Daniel Lin, Zhi-Yun Li, John J. Tobin, Nagayoshi Ohashi, Jes Kristian Jorgensen, eDisk Team

As part of the Early Planet Formation in Embedded Disks (eDisk) project, we present high resolution images of the edge-on Class I IRAS 04302+2247 disk in 1.3 mm (Band 6) using ALMA. With a resolution of 0.05” (8 au), the 1.3 mm continuum shows an asymmetry along the minor axis which is evidence for an optically thick and geometrically thick disk viewed nearly edge-on. There is no evidence of rings and gaps, which could be due to the lack of radial substructure or the highly inclined and optically thick view. Through radiative transfer modeling using RADMC3D, we find that the dust scale height is ~6 au at a radius of 100 au from the central star and is comparable to the gas pressure scale height. The results suggest that the dust of this Class I source has yet to vertically settle significantly. With 0.1” (16 au) resolution, we resolve the 2D snow surfaces of 12CO, 13CO, C18O, H2CO, and SO and find Keplerian rotation around a protostar of 1.6 Msun.