Radiation from Sources Moving in a Warm Magnetoplasma.
Abstract
The power lost through radiation by an electric charge as it spirals in a homogeneous magnetoplasma is calculated. Coherent Cerenkov radiation from a group of charges is studied by assuming the charges radiate as a single macroscopic ellipsoid of revolution having a uniform volume charge density. The total power radiated by such a macroscopic source is shown to be finite even in those cases where the refractive index is unbounded. The power radiated by electric dipole and loop antennas oriented with their axes along the magnetic field of an anisotropic plasma and moving parallel to this field are given in the form of integrals which are easily evaluated numerically. Mathematical models of the plasma dielectric tensor are derived using kinetic theory in addition to using the so-called hydrodynamic and full adiabatic theories (our Model H and A, respectively) with allowances made for the finite temperatures of both ions and electrons. Numerical results obtained using Models A and H are compared. For example, Model A predicts that in some cases a large fraction of the power radiated by a moving point charge source at frequencies near the upper hybrid resonance is in the form of thermal mode excitation. However, this 'high energy' thermal mode is missing from results obtained for the same source charge using Model H.
Document Details
- Document Type
- Technical Report
- Publication Date
- Apr 10, 1975
- Accession Number
- ADA010827
Entities
People
- Dennis John Baker
Organizations
- United States Naval Research Laboratory