An electron-cyclotron heating experiment on a medium-sized tokamak probes a point…

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

An electron-cyclotron heating experiment on a medium-sized tokamak probes a point where the electron density is

n_e = 6.0\times10^{19}\,\mathrm{m^{-3}}

, the magnetic field is

B_0 = 2.5\,\mathrm{T}

, and the launched wave frequency is

f = 105\,\mathrm{GHz}

. The bulk ions are deuterons,

m_i = 2m_p

. ((a)) Evaluate the five Stix functions

R

L

P

S

and

D

at this point, keeping only the electron contribution. ((b)) Calculate the cutoff frequencies

f_R

and

f_L

of the parallel R and L waves, with the ions neglected. ((c)) Calculate the upper hybrid frequency

f_{UH}

and, treating the ions as deuterons, the lower hybrid frequency

f_{LH}