Speaker
Description
Transition disks (TDs) are a type of protoplanetary disk characterized by an inner dust and gas cavity. The processes behind how these cavities are formed and maintained, along with the observed high accretion rates, continue to be subjects of active research. In our work, we aim to investigate if and how the inclusion of the Hall Effect alongside Ohmic Resistivity and Ambipolar Diffusion affects the TD. Of key interest is the behavior of the cavity and whether we can produce transonic accretion, as is predicted from observations. We performed 2D axisymmetric global R-MHD simulations of TD, with all three non ideal MHD effects and the inclusion of a PDR (photon dominated regime) module which provides a more realistic temperature structure in the disk. We use the Nirvana fluid code and have imposed a disk cavity in our disk. In total we performed three runs, for each configuration of the Hall effect: Hall aligned, Hall anti-aligned and Hall free. We find that for all three runs, our models reach a semi-steady state with an intact inner cavity and an outer standard disk. MHD winds are launched both from the cavity and from the disk. We get accretion rates typical of full disks and we observe (trans)sonic accretion in the cavity. Additionally, outward magnetic flux transport occurs in all three runs. Notably, when the Hall Effect is included, ring-like structures form within the cavity.
