Micro-ejections in star-disk resistive magnetohydrodynamic simulations
In simulations of a star-disk system in the closest vicinity of a star, we obtain very fast, light ejecta of matter. Those micro-ejections are of small mass and angular momentum flux, and can be launched from a resistive magnetosphere above the disk gap. Shown is the absolute value of toroidal current in code units, in logarithmic color grading. In solid lines are drawn poloidal magnetic field lines, with lines along which magnetic field vector points towards the star painted in black color, and those where the field points in the opposite direction, in white color. Reconnection is ongoing along the boundary sheet between the opposite-directed magnetic fields. The quasi-stationary state is reached, with matter pushed out of the magnetosphere by pressure gradient and magnetic forces, helped by reconnection. Vectors show poloidal velocity, normalized to Keplerian velocity at R=2.8 (for more details, see Cemeljic et al., 2013, ApJ768, 5).