Dust Concentration in Gas Substructures of Non-Ideal MHD Planet-Forming Disks

The discovery of rings and gaps in the disks around young stars was a significant breakthrough in planet formation. These disk substructures are essential because they gather dust particles, which are the building blocks of planets. However, how these substructures form in the magnetized disks where planets originate remains unclear. This limitation hampers our understanding of how planetary systems come into existence, including our own solar system. The research team plans to perform sophisticated computer simulations to gain deeper insights into this important problem. The simulations will shed light on how magnetic fields influence the formation of rings and gaps in the gaseous disk under realistic physical conditions, how these gas substructures give rise to the rings and gaps observed in dust emission, and how the distribution of dust impacts the overall dynamics of the disk. The program offers graduate and underrepresented undergraduate students valuable opportunities to participate in cutting-edge scientific research, contributing to the training of the next generation of scientists and promoting diversity within the STEM workforce. This research program builds on the preparatory work that has demonstrated the feasibility of forming rings and gaps in the lightly ionized gas of magnetized protoplanetary disks under simplifying assumptions. The team will improve on the initial work by incorporating more realistic physical processes, including the Hall effect, which is important for regulating the interaction between the magnetic field and lightly ionized gas. They will also couple the dynamics of the dust particles to that of the gas through aerodynamic drag and quantify how the dust distribution affects the ionization level of the gas, which, in turn, affects the overall dynamics of the magnetized disk. These improvements will significantly enhance our understanding of how a more realistic treatment of the disk physics impacts the formation of the rings and gaps in the gaseous disk. They will enable the research team to quantify whether the gas substructures can concentrate dust particles to the observed levels and evaluate the efficiency of the feedback of the particle distribution on the dynamics of the magnetized gas through its effects on ionization. The research program will improve our understanding of the origins of the rings and gaps that are ubiquitously observed in protoplanetary disks and key to planet formation. This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.