Role of cavitons in laser-plasma interactions: Final report for the period August 15, 1984-August 14, 1985

We have observed three new phenomena associated with cavitons generated at the critical layer in an inhomogeneous plasma. Half-harmonic [(1/2)ω0, (3/2)ω0, etc.] electromagnetic (em) radiation, accompanying the resonant absorption of the high-power microwave at ω0 by an inhomogeneous plasma, appears to originate from the cavitons. Double layers have been found to develop near the locations of cavitons. Acceleration of ions by these double layers has also been observed. The evolution of resonantly excited electron plasma waves and density profile modification at the critical layer has been studied in detail. Conditions under which the role of cavitons becomes significant in em wave-plasma interactions are discussed