A magnetised laboratory plasma has electron density in a uniform field

PHYSICS · Multi-part · Fermi University Physics · Plasma Physics · Waves in plasmas · Waves in plasmas

Plasma Physics, Ch Cold magnetised plasma waves: the dielectric tensor, cutoffs, resonances and the CMA diagram

Problem

A magnetised laboratory plasma has electron density

n_e = 5.0\times10^{18}\,\mathrm{m^{-3}}

in a uniform field

B_0 = 0.10\,\mathrm{T}

. Treat the ions as making a negligible contribution to

R

and

L

near these frequencies. ((a)) Calculate the electron plasma frequency

f_{pe}

and electron cyclotron frequency

f_{ce}

. ((b)) Calculate the cutoff frequencies

f_R

and

f_L

of the parallel R and L waves. ((c)) State how

f_{pe}

compares in size with

f_R

and

f_L