Spectral measurements from laser-produced plasma in OMEGA

Curved- and flat-diffraction crystal spectrographs were developed to collect x-ray spectra from high-atomic-number elements (cadmium-rare earths) in the 5-17-Å region. The plasma source was generated by the 24-beam, frequency-tripled light of the OMEGA laser system. The spectral patterns were identified with the aid of atomic structure calculations and from Moseley plots of isoelectronic sequences. The Ne-like (third-order diffraction) and Na-like ionization stages were observed in the Cd and Sn spectra. The rare-earth spectra were predominantly 3d-4p, 4f transitions over a range of ionization stages involving the M shell. Calibration spectra were obtained with L-series transitions from Fe and Cu targets and K lines from Si plasma excited in the glass supporting stalk.