  Relativistic plasma masers operating on the anomalous cyclotron-Cherenkov
resonance and the Cherenkov-drift resonance are capable of explaining the main
observational characteristics of pulsar radio emission.
  Both electromagnetic instabilities are due to the interaction of the fast
particles from the primary beam and from the tail of the secondary pairs
distribution with the normal modes of a strongly magnetized one-dimensional
electron-positron plasma. In a typical pulsar both resonances occur in the
outer parts of magnetosphere .
