Problem set 7, Due Wed 29. March 23, 2009 Typical plasma density in the Earth ionosphere is 104 106 cc. Explain the fact that kHz-type radio signal can "propagate around the Earth", while satellite communications use bands in hundreds of MHz. Consider plasma consisting of charges of the same mass (e.g. electron- positron plasma). 1. Calculate components of the dielectric tensor for plasma in magnetic eld . 2. Derive dispersion relation for parallel and perpendicular propagation. 3. Find polarization of normal modes. 4. For parallel and perpendicular propagation nd !(k) for both normal modes Consider plasma composed of in nitely heavy ions and electrons of zero mass (regime !B;i ! !B;e). Derive dispersion relation, phase and group velocity for waves propagating along magnetic eld . 1 ...