Heating and implosion of spherical targets irradiated by laser

The state of the art in implosion of shell targets by means of laser irradiation is reviewed, with emphasis on methods and results of evaluating the target compression parameters. The process begins with absorption of laser energy and heatup of the target, much information being provided by X-radiation from the corona region of the target plama. The Kal'mar 9-channel laser facility with a series parallel amplifier system was developed and subsequently modified for experimental study of laser fusion processes in targets. It consists of a YAG master laser with space filters and modulation, a short duration pulse shaping circuit, preamplifier stages, power amplifier stages, beam focusing and homing optics, and a vacuum chamber with diagnostic instruments. Spectral analysis and synthesis of laser radiation with the aid of a Fabry-Perot interferometer yielded data on the spectrum evolution and the intensity energy characteristics including time parameters and directivity as well as contrast.