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arXiv · 2201.10370

Linear pair creation damping of high frequency plasma oscillation

H. Al-Naseri·G. Brodin
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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.

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H. Al-Naseri, G. Brodin. 2022-01-25. Linear pair creation damping of high frequency plasma oscillation. https://doi.org/10.1063/5.0087085

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