[M-GI30] Computational sciences on the universe, galaxies, stars, planets and their environments

[MGI30-06] Collisional growth of dust in a turbulent protoplanetary disk

*Takashi Ishihara¹, Shohei Kawahara², Masayuki Umemura² (1.Okayama University, 2.University of Tsukuba)

Keywords:Dust growth, Turbulence, Direct numerical simulation, Protoplanetary disks

In the turbulent flow field of a protoplanetary disk, it has been thought that as dust particles grow in mass due to collisions, their increasing collision velocity prevents further growth. This idea is based on a theoretical evaluation of particle collision velocities in turbulence. However, particle collisional growth simulations using large-scale direct numerical simulations of turbulence, which allow only particles colliding below a critical velocity to grow, have shown that some particles repeatedly collide and grow below the critical velocity, suggesting that massive particles can form in an accelerated manner. This result indicates the need to reconsider the conventional scenario of dust growth in a turbulent protoplanetary disk. In this study, we aim to characterize the turbulent regions where particles can grow, by utilizing the results of particle collisional growth simulations (a database of turbulent fields and particles) based on large-scale direct numerical simulations of turbulence. Through this, we seek to construct a new scenario for dust growth in turbulent protoplanetary disks based on a deeper understanding of the phenomenon in turbulence.