Oral Presentation

Observational Hints for Efficient Ambipolar Diffusion in Disk Formation

Author(s): Hsi-Wei Yen (ASIAA) et al.

Presenter: Hsi-Wei Yen (ASIAA)

Circumstellar disks around young protostars are the birthplaces of planets, and their properties are closely linked to the planet formation process. ALMA observations have characterized hundreds of protostellar disks, yet the dominant mechanisms governing disk formation and evolution remain unclear. In this presentation, I will introduce our observational studies on the role of ambipolar diffusion in the disk formation process. Our results demonstrate that the disk size distribution observed with ALMA can be well explained by our model incorporating ambipolar diffusion. Furthermore, we observe an increasing mass-to-flux ratio from the dense core to the infalling protostellar envelope around a young protostar, consistent with theoretical predictions of efficient ambipolar diffusion. Additionally, our ALMA observations in the C18O and H13CO+ lines provide constraints on the ion-neutral drift velocity due to ambipolar diffusion.