End loss from a theta pinch

Based on the approximations of slow time variation and slow axial coordinate variation in an ideal magnetohydrodynamic flow, a simplified set of equations is obtained which applies to the problem of plasma outflow from a theta pinch. The characteristic speed of the flow, the signal speed, is the cusp wave speed. In this model, no high speed Alfvén waves are present in the low density region. An argument is presented indicating the existence of shocks in the low density outflow region. It is possible that such shocks may permit the analogy of hydrodynamic choking of the flow. A numerical scheme is described for computing a solution of the model equations. A sample computation gives plasma line density profiles and mass flux profiles for one particular case. The computation could not be carried out long enough to see pronounced shock effects in the main body of the plasma. The flow did not appear to approach a steady flow, but it did indicate the great effect of the flow in the throat on the remainder of the flow.