High intensity, subpicosecond XeCl laser: Laser physics and x-ray generation

Experiments performed with a terawatt-class laser system which is based on amplification in XeCl discharge amplifiers are described. Energy extraction in XeCl discharge amplifiers is examined experimentally and theoretically using 0.25-ps nearly transform limited pulses and both 16- and 75-ps strongly chirped pulses of the same bandwidth. We find that while the saturation fluence for the 16-ps pulse is comparable to that of the 0.25-ps pulse, stretching the pulse to a width of 75 ps increases the saturation fluence by 35%. A study of the interaction of the terawatt laser pulses with aluminum targets at irradiances exceeding 5×10¹⁸ W/cm² is also presented.