The Role of Coagulation in The Dynamics of Dust Grains and Small Bodies in Accretion Disks of Young Stars

The paper investigates the influence of coagulation on the dynamics of dust particles in the accretion disks of young stars. Key processes, including radial drift, sedimentation, and particle growth due to coagulation, are considered. The evolution of the radial velocity and particle sizes, as well as the timescales of sedimentation and radial drift, are analyzed for cases with and without coagulation. It is shown that coagulation reduces both sedimentation and radial drift times, accelerating the particles’ movement toward the star. However, near the inner edge of the disk, particle growth is constrained by the fragmentation threshold.