Pulsars: Progress, Problems and Prospects

Abstract

I survey recent successes in the application of relativistic MHD and force-free electrodynamics to the modeling of the pulsars' rotational energy loss mechanism as well as to the structure and emission characteristics of Pulsar Wind Nebulae. I suggest that unsteady reconnection in the current sheet separating the closed from the open zones of the magnetosphere is responsible for the torque fluctuations observed in some pulsars, as well as for departures of the braking index from the canonical value of 3. I emphasize the significance of the boundary layer between the closed and open zones as the active site in the outer magnetopshere. I elaborate on the conflict between the models currently in use to interpret the gamma ray and X-ray pulses from these systems with the electric current flows found in the spin down models. Because the polar cap ``gap'' is the essential component in the supply of plasma to pulsar magnetospheres and to pulsar wind nebulae, I emphasize the importance of high sensitivity gamma ray observations of pulsars with core components of radio emission and high magnetospheric voltage, since these observations will look directly into the polar plasma production region. I also discuss the shock conversion of flow energy into the spectra of the synchrotron emitting particles in the Nebulae. I comment on the prospects for future developments and improvements in all these areas.