A Tale of Two Current Sheets

TL;DR

This paper proposes a new model for particle acceleration in pulsar magnetospheres involving reconnection at the light cylinder and auroral acceleration, addressing the sigma problem through increased pair outflows and magnetic dissipation.

Contribution

It introduces a novel model of particle acceleration in pulsar current sheets, emphasizing reconnection and auroral processes, and links recent pulsar wind studies to the sigma problem.

Findings

Pair outflow rates exceed existing pair creation predictions.

Magnetic field dissipation in the wind helps solve the sigma problem.

Lower wind velocities result from increased mass loading.

Abstract

I outline a new model of particle acceleration in the current sheet separating the closed from the open field lines in the force-free model of pulsar magnetospheres, based on reconnection at the light cylinder and "auroral" acceleration occurring in the return current channel that connects the light cylinder to the neutron star surface. I discuss recent studies of Pulsar Wind Nebulae, which find that pair outflow rates in excess of those predicted by existing theories of pair creation occur, and use those results to point out that dissipation of the magnetic field in a pulsar's wind upstream of the termination shock is restored to life as a viable model for the solution of the "$\sigma$" problem as a consequence of the lower wind 4-velocity implied by the larger mass loading.