Force-free pulsar magnetospheres

The equations to the steady, axisymmetric, charged pulsar magnetosphere given recently by Michel (1973a, b) and Scharlemann and Wagoner (1972, preprint) are generalized to non-axisymmetric systems that are steady in the frame rotating with the pulsar. It is shown that in all nonsingular models with cylindrical (but not axial) symmetry, and with a non-zero magnetic field component parallel to the axis, the magnetic field lines emanating from the pulsar are all trapped within the light-cylinder, so that there is no net electromagnetic energy flow across the light cylinder.