Spatially and spectrally resolved filamentary structures in the (3/2)omega 0 emission from laser produced plasmas

Technical Report ·

OSTI ID:5889926

Lin, Z; Willi, O; Rumsby, P T

This study was conducted to explore the problem of filamentation of laser light in the underdense plasma corona surrounding ablatively imploded spherical targets, a phenomenon which may prevent the realization of laser-driven fusion schemes. Preliminary observations were made of filamentary structures in the (3/2)(omega sub o) emission from microballoon targets irradiated in the ablative mode. Time integrated spectroscopy showed double and single peaked (3/2)(omega sub o) emission spectra. A simple model for the growth and collapse of filaments was based on the movement of the density contours at the bottom of the filament with large velocity. Here the laser intensity was high and various decay instabilities and scattering processes took place. In particular the two plasmon decay instability occurred where the electron density was nc/4, a region of (3/2)(omega sub o) emission. The model was consistent with the experimentally observed spectra and predicted the type of omega sub o and 2 omega sub o that should be observed in future experiments.

• Research Organization: Science and Engineering Research Council, Chilton (UK). Rutherford Appleton Lab.
• OSTI ID: 5889926
• Report Number(s): PB-83-165969
• Country of Publication: United States
• Language: English

Related Subjects

70 PLASMA PHYSICS AND FUSION TECHNOLOGY
700208* -- Fusion Power Plant Technology-- Inertial Confinement Technology
ABLATION
DECAY INSTABILITY
ELECTROMAGNETIC RADIATION
EXPANSION
IMPLOSIONS
INSTABILITY
LASER IMPLOSIONS
LASER RADIATION
LASER TARGETS
LASER-PRODUCED PLASMA
MATHEMATICAL MODELS
MICROSPHERES
PLASMA
PLASMA EXPANSION
PLASMA INSTABILITY
PLASMONS
QUASI PARTICLES
RADIATIONS
TARGETS