Non-linear 3D simulations of current-driven instabilities in jets

We present global 3D nonlinear simulations of the Tayler instability in the presence of vertical fields. The initial configuration is in equilibrium, which is achieved by a pressure gradient or an external potential force. The non linear evolution of the system leads to a stable equilibrium with a current free toroidal field. We find the that presence of a vertical poloidal field stabilize the system if Bϕ≈Bz. The implication of our findings for the physics of astrophysical jets are discussed.