# Accession Number:

## AD0285384

# Title:

## THE WAKE OF A CHARGED PARTICLE MOVING THROUGH A PLASMA WITH MAGNETIC FIELD

# Descriptive Note:

# Corporate Author:

## MASSACHUSETTS INST OF TECH CAMBRIDGE RESEARCH LAB OF ELECTRONICS

# Personal Author(s):

# Report Date:

## 1962-09-14

# Pagination or Media Count:

## 1.0

# Abstract:

The motion of a charged particle through a lowdensity electron plasma placed in an external constant magnetic field has been investigated by using transport equations. The motion of the particle in the direction of the applied magnetic field is considered in detail the particles moving at right angles to the magnetic field are considered briefly. The charge density developed in the medium as a result of interaction of the medium with the moving particle through longrange Coulomb force is evaluated for the wavelength, Lambda, which is such that R is greater than Lambda is greater than Lambda D, where R is the distance from the moving particle, and Lambda D, the Debye wavelength. Three types of charge-density waves are associated with the moving test particle. One is a plasma electron wave that exists only for velocities of the test particle that are greater than the average thermal speed of the plasma electron this wave also shows a Mach cone distribution. The second is an elliptically shaped extraordinary electromagnetic wave that exists for all velocities of the test particle, and is coupled to the plasma electron wave. The third is an almost spherical weak wave associated with the ordinary electromagnetic wave. This third wave is not coupled to the other two waves within the range of approximation considered here, and it goes over to an exponentially decreasing charge distribution in the limit of very small magnetic field. Author