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| EPoS Contribution |
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Disk Growth and Angular Momentum Transfer at the Early Stage of Star Formation
Hsi-Wei Yen ESO, Munich, DE | |
| To study how protostellar disks form and grow, we observed gas kinematics on scales from thousands of au to 100 au with single-dish telescopes, SMA, and ALMA. With the kinematical information, we measured protostellar masses, disk sizes, and radial profiles of specific angular momentum in a sample of protostars. Combining our measurements and those from the literature, our results could suggest that the Keplerian disk radius quickly grows from <10 au to ~100 au as the protostellar mass increases from <0.1 Msun to ~0.2 Msun, and the disk growth rate slows down in the Class I stage. In addition, the more evolved protostellar sources tend to exhibit a higher specific angular momentum on a scale of hundreds of au. The sign of disk growth and the evolutionary trend of the angular momentum profiles revealed with our observations can be explained with inside-out collapse models. Nevertheless, we also found hints of magnetic braking removing angular momentum from collapsing material in individual sources. | |
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| Caption: (a) Protostellar mass versus disk radius for a sample of protostars. Blue diamonds and red squares present the Class I and 0 protostars. (b) Radial profiles of specific angular momenta in a sample of protostars (colors), in comparison with the expected profiles computed from inside-out collapse models for protostellar masses of 1.0, 0.4, and 0.1 Msun from top to bottom. (grey dashed curves). Numbers in colors label the measured protostellar masses of the sample protostars. | |
| Collaborators: P.M. Koch, ASIAA, TW S. Takakuwa, Kagoshima U, JP R. Krasnopolsky, ASIAA, TW N. Ohashi, NAOJ, JP Y. Aso, ASIAA, TW |
Key publication
Suggested Session: Protostellar disks |