Electric field screening in pair discharges and generation of pulsar radio emission

TL;DR

This paper presents an analytic model of electric field screening in pair discharges within pulsar magnetospheres, explaining observed radio luminosity and spectrum through a three-stage discharge process.

Contribution

It introduces a simplified analytic theory for electric field screening in pulsar pair discharges, linking discharge dynamics to radio emission characteristics.

Findings

Estimated pulsar radio luminosity around 10^{28} erg/s.

Predicted radio spectrum slope approximately -1.4.

Described three discharge stages: initial screening, nonlinear damping, and linear phase.

Abstract

Pulsar radio emission may be generated in pair discharges which fill the pulsar magnetosphere with plasma as an accelerating electric field is screened by freshly created pairs. In this Letter we develop a simplified analytic theory for the screening of the electric field in these pair discharges and use it to estimate total radio luminosity and spectrum. The discharge has three stages. First, the electric field is screened for the first time and starts to oscillate. Next, a nonlinear phase occurs. In this phase, the amplitude of the electric field experiences strong damping because the field dramatically changes the momenta of newly created pairs. This strong damping ceases, and the system enters a final linear phase, when the electric field can no longer dramatically change pair momenta. Applied to pulsars, this theory may explain several aspects of radio emission, including the observed luminosity, $L_{\rm{rad}} \sim 10^{28} \rm{erg} \, \rm{s}^{-1}$, and the observed spectrum, $S_\omega \sim \omega^{-1.4 \pm 1.0} $.