TY - JOUR

T1 - Early Planet Formation in Embedded Disks (eDisk). II. Limited Dust Settling and Prominent Snow Surfaces in the Edge-on Class I Disk IRAS 04302+2247

AU - Lin, Zhe Yu Daniel

AU - Li, Zhi Yun

AU - Tobin, John J.

AU - Ohashi, Nagayoshi

AU - Jørgensen, Jes Kristian

AU - Looney, Leslie W.

AU - Aso, Yusuke

AU - Takakuwa, Shigehisa

AU - Aikawa, Yuri

AU - van’t Hoff, Merel L.R.

AU - de Gregorio-Monsalvo, Itziar

AU - Encalada, Frankie J.

AU - Flores, Christian

AU - Gavino, Sacha

AU - Han, Ilseung

AU - Kido, Miyu

AU - Koch, Patrick M.

AU - Kwon, Woojin

AU - Lai, Shih Ping

AU - Lee, Chang Won

AU - Lee, Jeong Eun

AU - Phuong, Nguyen Thi

AU - Sai (Insa Choi), Jinshi

AU - Sharma, Rajeeb

AU - Sheehan, Patrick

AU - Thieme, Travis J.

AU - Williams, Jonathan P.

AU - Yamato, Yoshihide

AU - Yen, Hsi Wei

N1 - Funding Information: We thank the reviewer for the constructive comments. Z.-Y.D.L. acknowledges support from NASA 80NSSC18K1095, the Jefferson Scholars Foundation, the NRAO ALMA Student Observing Support (SOS) SOSPA8-003, the Achievements Rewards for College Scientists (ARCS) Foundation Washington Chapter, the Virginia Space Grant Consortium (VSGC), and UVA research computing (RIVANNA). Z.-Y.L. is supported in part by NASA 80NSSC18K1095 and NSF AST-1910106. J.J.T. acknowledges support from NASA 21-XRP21-0064 and XRP 80NSSC22K1159. N.O. and C.F. acknowledge support from the National Science and Technology Council (NSTC) in Taiwan through grants NSTC 109-2112-M-001-051 and 110-2112-M-001-031. J.K.J. acknowledges support from the Independent Research Fund Denmark (grant No. 0135-00123B). L.W.L. acknowledges support from NSF AST-2108794. S.T. is supported by JSPS KAKENHI grant Nos. 21H00048 and 21H04495 and by NAOJ ALMA Scientific Research grant No. 2022-20A. Y.A. acknowledges support by NAOJ ALMA Scientific Research Grant code 2019-13B, Grant-in-Aid for Scientific Research (S) 18H05222, and Grant-in-Aid for Transformative Research Areas (A) 20H05844 and 20H05847. M.L.R.H. acknowledges support from the Michigan Society of Fellows. I.d.G. acknowledges support from grant PID2020-114461GB-I00, funded by MCIN/AEI/10.13039/501100011033. F.J.E. acknowledges support from NSF AST-2108794. S.G. acknowledges support from the Independent Research Fund Denmark (grant No. 0135-00123B). P.M.K. acknowledges support from NSTC 108-2112- M-001-012, NSTC 109-2112-M-001-022, and NSTC 110-2112-M-001-057. S.-P.L. and T.J.T. acknowledge grants from the National Science and Technology Council of Taiwan 106-2119-M-007-021-MY3 and 109-2112-M-007-010-MY3. W.K. was supported by the National Research Foundation of Korea (NRF) grant funded by the Korea government (MSIT) (NRF-2021R1F1A1061794). C.W.L. is supported by the Basic Science Research Program through the National Research Foundation of Korea (NRF) funded by the Ministry of Education, Science and Technology (NRF- 2019R1A2C1010851) and by the Korea Astronomy and Space Science Institute grant funded by the Korea government (MSIT; project No. 2022-1-840-05). J.-E.L. was supported by the National Research Foundation of Korea (NRF) grant funded by the Korean government (MSIT) (grant No. 2021R1A2C1011718). R.S. acknowledges support from the Independent Research Fund Denmark (grant No. 0135-00123B). P.D.S. acknowledges support from NSF AST-2001830 and NSF AST-2107784. J.P.W. acknowledges support from NSF AST-2107841. Y.Y. is supported by the International Graduate Program for Excellence in Earth-Space Science (IGPEES), World-leading Innovative Graduate Study (WINGS) Program of the University of Tokyo. H.-W.Y. acknowledges support from the National Science and Technology Council (NSTC) in Taiwan through grant NSTC 110-2628-M-001-003-MY3 and from the Academia Sinica Career Development Award (AS-CDA-111-M03). Publisher Copyright: © 2023. The Author(s). Published by the American Astronomical Society.

PY - 2023/6/28

Y1 - 2023/6/28

N2 - While dust disks around optically visible, Class II protostars are found to be vertically thin, when and how dust settles to the midplane are unclear. As part of the Atacama Large Millimeter/submillimeter Array large program, Early Planet Formation in Embedded Disks, we analyze the edge-on, embedded, Class I protostar IRAS 04302+2247, also nicknamed the “Butterfly Star.” With a resolution of 0.″05 (8 au), the 1.3 mm continuum shows an asymmetry along the minor axis that is evidence of 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. With 0.″1 (16 au) resolution, we resolve the 2D snow surfaces, i.e., the boundary region between freeze-out and sublimation, for 12CO J = 2-1, 13CO J = 2-1, C18O J = 2-1, H 2CO J = 30,3-20,2, and SO J = 65-54, and constrain the CO midplane snow line to ∼130 au. We find Keplerian rotation around a protostar of 1.6 ± 0.4 M ⊙ using C18O. Through forward ray-tracing using RADMC-3D, 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.

AB - While dust disks around optically visible, Class II protostars are found to be vertically thin, when and how dust settles to the midplane are unclear. As part of the Atacama Large Millimeter/submillimeter Array large program, Early Planet Formation in Embedded Disks, we analyze the edge-on, embedded, Class I protostar IRAS 04302+2247, also nicknamed the “Butterfly Star.” With a resolution of 0.″05 (8 au), the 1.3 mm continuum shows an asymmetry along the minor axis that is evidence of 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. With 0.″1 (16 au) resolution, we resolve the 2D snow surfaces, i.e., the boundary region between freeze-out and sublimation, for 12CO J = 2-1, 13CO J = 2-1, C18O J = 2-1, H 2CO J = 30,3-20,2, and SO J = 65-54, and constrain the CO midplane snow line to ∼130 au. We find Keplerian rotation around a protostar of 1.6 ± 0.4 M ⊙ using C18O. Through forward ray-tracing using RADMC-3D, 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.

U2 - 10.3847/1538-4357/acd5c9

DO - 10.3847/1538-4357/acd5c9

M3 - Journal article

AN - SCOPUS:85163853238

VL - 951

JO - Astrophysical Journal

JF - Astrophysical Journal

SN - 0004-637X

IS - 1

M1 - 9

ER -