In the absence of a magnetic field electromagnetic waves can propagate in plasma only at frequencies higher than the plasma frequency. Waves at frequencies below the plasma frequency are reflected from the plasma boundaries. They can only penetrate a small distance of order c/ω0. In the presence of a magnetic field waves polarized with their electric fields parallel to the constant external magnetic field behave in a similar manner. The magnetic field does not affect these waves.† The plasma particles move in the direction of the electric field and the magnetic field, which is also in this direction, exerts no influence on their motion.
Unable to display preview. Download preview PDF.