Thermal and impulse coupling to an aluminum surface by a pulsed KrF laser

The amount of heat deposited on an aluminum target after irradiation in air by a KrF laser at 249 nm has been measured to be ∼40% of the incident pulse energy for long pulses (0.5 μsec), moderate flux levels (106–108 W/cm2), and spot diameter ⩾0.5 cm. The impulse generated by the laser has also been measured. Significant impulse levels were observed at low incident fluence levels.