rotating electrons are captured from the plasma wind through the leaky magnetopause and as shown in the left create a current disc shown as transparent red in the figure with darker shading indicating greatest density near the coil pair and extending out to the magnetopause radius Rmp, which is orders of magnitude larger than the coil radius Rc (figure not drawn to scale). See RMDCartoon.avi for an animation of this effect. The induced current disc carries a direct current (A) orders of magnitude larger than the input alternating current (A) and forms a static dipole magnetic field oriented perpendicular to the current disc reaching a standoff balance with the plasma wind pressure at distance at the magnetopause boundary according to the MHD model of an artificial magnetosphere. The magnetic field falloff rate was assumed to be =1 is described in detail in, but as described by Khazanov, restated by Kirtley and Slough and several MPS studies concluded that is closer to 2. The falloff rate is a critical parameter in the determination of performance. The RMF-induced rotating disc of electrons has current density (A/m2) at distance r from the antenna as given by equation (5) for and equation (4) for , which states that flux conservation requires this falloff rate, consistent with a criticism of M2P2 by Cattell as follows: where (T) is the magnetic field at radius (m) near the antenna coils. Note that the current density is highest at and falls off at a rate of . A critical condition for the plasma magnet design from equation (1a) provides a lower bound on the RMF frequency (rad/s) as follows so that electrons in the plasma wind are magnetized and rotate but the ions are not magnetized and do not rotate: where (rad/s) is the ion gyrofrequency in the RMF near the antenna coils, is charge number of the ion, (C) is the elementary charge, and (kg) is the (average) mass of the ion(s). Specifying the magnetic field near the coils at radius is critical since this is where the current density is greatest. Choosing a magnetic field at magnetopause yields a lower value of but ions closer to the coils will rotate. Another condition is that be small enough such that collisions are extremely unlikely. The required power to generate the RMF is derived by integrating the product of the square of the current density from equation and