Satellite spectral lines in high density laser-produced plasmas

Two types of satellite lines are studied in laser-produced plasmas as potential diagnostic tools. One consists of a pair of lines straddling the wavelength of a dipole-forbidden line and displaced from it by the laser frequency. The relative intensities are a measure of the local laser electric field in the plasma. Possible satellites of this sort associated with He-like and Li-like magnesium n = 2 to n = 3 transitions are indicated in the data. The second type of satellite arises from an innershell transition in Li-like aluminum (and magnesium) and the lines occur adjacent to the He-like ls2 1S-ls3p 1P x-ray resonance line. The upper level configuration for one satellite does not readily autoionize, and hence is populated mainly by electron collisions in a high density plasma. It is an electron density indicator, and in the present case the relative intensity is consistent with electron densities ~ 1020 cm−3, according to atomic physics modeling. The wavelengths of these Li-like innershell satellites appear to be shifted shorter by ~ 13 mÅ when compared to those of nearby He-like resonance lines. The sequence of such ionic x-ray lines from streak data are in agreement with a numerical code.