Research Highlights

Magnetospheric Accretion and Ejection of Matter in Resistive MHD Simulations

In numerical simulations of the star-disk system, after the relaxation, the disk is truncated at the truncation radius R_t. Position of the R_t is close to the line of balance of the disk ram pressure and the magnetic pressure, which is located between a central object and the disk inner radius.

Čemeljić, Shang H and Chiang T-Y, submitted to ApJ, arXiv:1112.6226

We show the quasi-stationary result in our simulation in the snapshot taken after few hundred rotations of the disk inner radius. To show the difference between density and mass flux plots, the left half of the panel shows the poloidal mass flux $\rho {\rm v_p}$, and the right half shows the density. Both plots are in logarithmic color scales, shown at the bottom of the panels. The poloidal magnetic field lines are shown in solid white lines, with lines in the axial region omitted, to show velocities in white arrows. We measure the position of disk truncation radius by the steep drop in the disk density which occurs at R_t=3.0R_*, which is marked in the figure by a black arrow. Position of the R_t does not match any of the values suggested in the literature, and it is the topic of our current research.