Electron outflow in pulsar magnetospheres

The formalism introduced by Mestel et al. (1984) to model the acceleration of electrons leaving a pulsar along the magnetic-field lines is investigated analytically. Four classes of flow are identified by considering the divergence of the Lorentz factor gamma for dissipation-free flow with significant emission speed. Three of the classes are physically continuous and correspond to rapid acceleration inside, on, and outside the light cylinder, respectively; a fourth class is characterized by no divergence of gamma and hence no rapid acceleration of the flow, which is governed by the model equations throughout. The need for a global solution to determine which of these classes actually occurs in pulsar magnetospheres is indicated.