Nonequilibrium plasma radiation emitted from laser targets

An investigation was made of the emission characteristics of laser targets in the soft x-ray region where the principal mechanisms determining the spectrum are photorecombination, bremsstrahlung, and discrete spectral transitions. A radiative-collisional model was used to describe the states of a laser target plasma. The characteristics obtained by solving the kinetic problem were used to calculate the absorption and emission coefficients. The transport equation was solved for a set of instants of time with a specified field of the gasdynamic parameters and detailed information was obtained on the spectral composition of the output radiation and on its temporal evolution. The effective radiation temperatures and the radiation losses were determined. A comparison was made between the integrated emission parameters obtained by solving the transport equation and by using the volume emission approximation.