Linear pair creation damping of high frequency plasma oscillation

TL;DR

This paper investigates a novel damping mechanism for high-frequency plasma oscillations caused by electron-positron pair creation, using a quantum field theoretical approach to extend traditional plasma wave analysis.

Contribution

It introduces a new pair-creation damping mechanism for Langmuir waves in high-density plasmas based on the Dirac-Heisenberg-Wigner formalism, including analysis of its dependence on plasma parameters.

Findings

Damping rate depends on wave-number, temperature, and density.

Vacuum contributions are small after charge renormalization.

The theory aligns with previous vacuum polarization results.

Abstract

We have studied the linear dispersion relation for Langmuir waves in plasmas of very high density, based on the Dirac-Heisenberg-Wigner formalism. The vacuum contribution to the physical observables leads to ultra-violet divergences, that are removed by a charge renormalization. The remaining vacuum contribution is small, and is in agreement with previously derived expressions for the time-dependent vacuum polarization. The main new feature of the theory is a damping mechanism similar to Landau damping, but where the plasmon energy give rise to creation of electron-positron pairs. The dependence of the damping rate (pair-creation rate) on wave-number, temperature, and density is analyzed. Finally, the analytical results of linearized theory are compared.