演講資訊

摘要：

Planet formation begins with the evolution of micron-sized dust grains into kilometer-sized planetesimals in a protoplanetary disk around a young star. Turbulence in protoplanetary disks plays a key role in dust evolution and planetesimal formation. One possible source of turbulence is the vertical shear instability (VSI), which can develop when gas cools quickly. Interestingly, dust particles not only respond to VSI-driven turbulence but also affect the cooling and potentially regulate turbulence itself. In this talk, I present results from global two-dimensional simulations including gas and dust to investigate this interaction. We find that VSI mixing, dust settling, and the local dust cooling reach an equilibrium, forming a thick dust layer. This balance is strongly dependent on dust size and the dust-to-gas mass ratio. Larger grains or lower mass ratios weaken the turbulence, leading to dust settling. Our results suggest that the efficiency of dust growth can depend on the VSI in protoplanetary disks. I will also discuss possible implications for disk observations and further planet formation. This talk is based on my recent work (Fukuhara et al. 2025).