CRITICAL-REVIEW OF THE PLASMA-MASER INSTABILITY

Several key points of the plasma maser are critically reviewed. The to tal momentum and energy conservation relations for the plasma-maser in teraction among the resonant and nonresonant modes, and the electrons are satisfied for magnetized plasma The plasma maser satisfies the gen eralized Manley-Rowe relation, which includes the effective action fro m resonant electrons in addition to the original one from waves. A dia grammatic approach to the theory of the plasma maser is given, The pla sma maser corresponds to the vertex correction in contrast to the reso nance broadening effect which corresponds to the propagator correction . The plasma-maser contribution from polarization term for magnetized plasma is investigated. A correct transition from the magnetized to ze ro magnetic held case is presented for electrostatic waves. The import ance of the symmetry breaking due to the external magnetic field on th e plasma maser instability is stressed.