Unstable spectrum of a relativistic electron beam interacting with a quantum collisional plasma: application to the Fast Ignition Scenario

TL;DR

This paper investigates how quantum and collisional effects influence the unstable spectrum of a relativistic electron beam in a plasma, with implications for the Fast Ignition Scenario, highlighting the impact of electron-ion collisions on instability modes.

Contribution

It introduces a two-fluids model to analyze quantum and collisional effects on beam-plasma instabilities in the Fast Ignition context, revealing the significant role of electron-ion collisions.

Findings

Electron-ion collisions induce larger wavelength oblique unstable modes.

Transition from collisionless to resistive regime is discontinuous.

Partial degeneracy effects are negligible.

Abstract

Quantum and collisional effects on the unstable spectrum of a relativistic electron beam-plasma system are investigated through a two-fluids model. Application is made to the near target center interaction of the relativistic electron beam in the Fast Ignition Scenario. Partial degeneracy effects are found negligible while the most influential factors are the beam temperature and the electron-ion collision frequency of the plasma. The introduction of the latter triggers some oblique unstable modes of much larger wave length than the collisionless ones. Transition from the collisionless regime to the resistive one is thus documented and found discontinuous.