Multidimensional electron beam-plasma instabilities in the relativistic regime

Multidimensional electron beam-plasma instabilities in the relativistic regime

Instabilities for a relativistic electron beam interacting with a laser-irradiated plasma.

The effects of a radiation field (RF) on the unstable modes developed in a relativistic electron beam-plasma interaction are investigated assuming that ω(0) > ω(p), where ω(0) is the frequency of the RF and ω(p) is the plasma frequency. These unstable modes are parametrically coupled to each other due to the RF and are a mix between two-stream and parametric instabilities. The dispersion equati...

Relativistic particle acceleration in an electron-positron plasma with a relativistic electron beam

Results from three-dimensional electromagnetic particle simulations of an electron-positron plasma with a relativistic electron beam (y=2) are presented. As part of the initial conditions, a poloidal magnetic field is specified, consistent with the current carried by the beam electrons. The beam undergoes pinching oscillations due to the pressure imbalance. A transverse two-stream instability i...

The theory and simulation of relativistic electron beam transport in the ion-focused regime

Several recent experiments involving relativistic electron beam (REB) transport in plasma channels show two density regimes for efficient transport; a low-density regime known as the ion-focused regime (IFR) and a high-pressure regime. The results obtained in this paper use three separate models to explain the dependency of REB transport efficiency on the plasma density in the IFR. Conditions f...

Electromagnetic instabilities for relativistic beam-plasma interaction in whole k space: nonrelativistic beam and plasma temperature effects.

For the system formed by a relativistic electron beam and its plasma return current, we investigate the effects of both transverse and parallel beam and plasma temperatures on the linear stability of collective electromagnetic modes. We focus on nonrelativistic temperatures and wave-vector orientations ranging from two-stream to filamentation instabilities. Water-bag distributions are used to m...