Induced absorption of extraordinary (Z-mode) waves via electron pumping

When induced by pitch-angle scattering, waves of the middle branch of the extraordinary mode will give up their energy to a plasma by magnetically pumping electrons. The damping decrement for small-amplitude extraordinary waves is calculated and the decrement for finite-amplitude waves is estimated. Because heating a plasma makes it a better absorber of extraordinary waves, such waves can produce localized hot cavities in plasmas. The evolution of electron distribution functions f(v) is examined and it is found that magnetic-pumping-mediated absorption leads to fproportionalv-3 tails