The properties of charge-separated pulsar magnetospheres

The general properties of a cold charge-separated plasma are investigated, including both electromagnetic and inertial effects. There is found to be a ‘magneto-vortex’ vector which is frozen into the plasma and an equation similar in form to the ‘force-free’ condition is established. An aligned rotator model is considered and general expressions for its energy, angular momentum and particle loss are derived. An extension of Ferraro's law of isorotation is also proved. Finally, through comparing the plasma equations to those of a rotating fluid, a ‘magnetic Rossby number’ is defined which, when small, leads to the formation of magnetic Taylor columns and the propagation of ‘magneto-inertial’ waves. General wave propagation is briefly discussed.