Influence of laser radiation wavelength on parameters of forming plasma

A wide range of laser radiation quantum energies epsilon sub 0 = 1 - 300 eV is investigated for moderate flux densities (10 to the 8th power - 10 to the 10th power w/sq cm.) and durations of up to 0.1 - 1 micro sec in support of a theoretical study of the processes underlying the interaction of monochromatic radiation at different wavelengths with a barrier. Inverse brehmsstrahlung is found to be the dominant mechanism for longwave radiation. The absorption of harder radiation by vapor at low temperatures is determined by photoionization. In the constant-mass heating condition, the plasma temperature is found to increase rapidly; as the quantum energy increases the plasma temperature drops and the pressure increases on the surface of the obstacle. The estimates and numerical calculations indicate that the plasma parameters vary nonmonotonically as the laser radiation quantum energy.