Plasma electron-hole kinematics: momentum conservation

TL;DR

This paper provides an analytic framework for understanding the momentum conservation and kinematic behavior of plasma electron holes, explaining observed phenomena like self-acceleration and ion interactions.

Contribution

It introduces a comprehensive analytic model for plasma electron hole kinematics based on momentum conservation principles.

Findings

Analytic calculation of momentum changes in plasma electron holes

Explanation of self-acceleration and hole-ion interactions

Alignment with numerical simulation observations

Abstract

We analyse the kinematic properties of a plasma electron hole: a non-linear self-sustained localized positive electric potential perturbation, trapping electrons, that behaves as a coherent entity. When a hole accelerates or grows in depth, ion and electron plasma momentum is changed both within the hole and outside it, by an energization process we call jetting. We present a comprehensive analytic calculation of the momentum changes of an isolated general one-dimensional hole. The conservation of the total momentum gives the hole's kinematics, determining its velocity evolution. Our results explain many features of the behavior of hole speed observed in numerical simulations, including self-acceleration at formation, and hole pushing and trapping by ion streams.