Pressure and impulse on an aluminium target from pulsed laser irradiation at reduced ambient pressure

An experimental investigation of the time-dependent pressure induced on an aluminium target from a pulsed CO2 laser irradiation at reduced ambient density has been made. As the pressure of the air surrounding the target decreases from 760 to 0.5 Torr, the width of the pressure pulse on the target becomes narrower, and the amplitude of the pressure increases. A pressure as high as 1.7 kbar and a mechanical coupling of 20 dyn sec J are obtained.