Electromagnetic waves destabilized by runaway electrons in near-critical electric fields
Artikel i vetenskaplig tidskrift, 2013

Runaway electron distributions are strongly anisotropic in velocity space. This anisotropy is a source of free energy that may destabilize electromagnetic waves through a resonant interaction between the waves and the energetic electrons. In this work, we investigate the high-frequency electromagnetic waves that are destabilized by runaway electron beams when the electric field is close to the critical field for runaway acceleration. Using a runaway electron distribution appropriate for the near-critical case, we calculate the linear instability growth rate of these waves and conclude that the obliquely propagating whistler waves are most unstable. We show that the frequencies, wave numbers, and propagation angles of the most unstable waves depend strongly on the magnetic field. Taking into account collisional and convective damping of the waves, we determine the number density of runaways that is required to destabilize the waves and show its parametric dependences.

Författare

A Kómár

Budapesti Muszaki es Gazdasagtudomanyi Egyetem

Gergö Pokol

Budapesti Muszaki es Gazdasagtudomanyi Egyetem

Tünde Fülöp

Chalmers, Teknisk fysik, Nukleär teknik

Physics of Plasmas

1070-664X (ISSN) 1089-7674 (eISSN)

Vol. 20 012117- 012117

Drivkrafter

Hållbar utveckling

Styrkeområden

Energi

Fundament

Grundläggande vetenskaper

Ämneskategorier

Fusion, plasma och rymdfysik

DOI

10.1063/1.4776666