Abstract

Plasmas have been experimentally diagnosed produced by line-focused laser light (1064 nm, 1-20 J, 250 ps; and 0.1 x 3.5-mm focal line) irradiated planar and thin cylindrical targets. In the experiments the principal plasma diagnostics included microphotographic diagnoses of fundamental and harmonic emissions, picosecond interferometry, and shadow photography using a stimulated Raman backscattering probe beam, Faraday cups, space-resolved and space-integrated x-ray crystal spectrometers, and x-ray pinhole cameras, etc. The experimental results indicate that the space anisotropy of the ion emission from line-focused laser-produced plasma is more noticeable than that from generally spot-focused laser-produced plasma. The ion peak due to the ions accelerated by the resonantly driven electrostatic field also is more obvious. For high Z (such as Au) targets, we have observed for the first time line-focused laser beam filamentation in plasmas. The plasma jetlike structures have also been seen using optical probing techniques. In addition, the x-ray line spectra emitted from line-focused laser plasmas also display the characteristics of the spectral lines being remarkably broadened due to the large source size.

© 1986 Optical Society of America