Spectroscopic investigations of the x-ray emission of plasmas heated by 120 ps, frequency doubled pulses from the JANUS Nd:glass laser are presented. High Z K-shell spectra emitted from slab targets heated to near 1017 W cm-2 intensity are investigated. High resolution ((lambda) /$DELTA(lambda) > 5000) x-ray spectra of multicharged ions of He-like Ti, Co, Ni, Cu, and also H-like Sc in the spectral range 1.5-3.0 angstrom are obtained in single laser shots using a spherically bent Mica crystal spectrograph with a 186 mm radius of curvature. The spectra have 1D spatial resolution of about 25 micrometers and indicate that the size of the emission zone of the resonance transitions is < 25 micrometers . Simultaneous x-ray images of the plasma from a charge-coupled device pinhole camera confirmed that the plasma x-ray emission is from a similar sized source. Survey spectra ((lambda) /(Delta) (lambda) equals 500 - 1000) taken with a flat LiF (200) crystal spectrometer with a charge-coupled device detector complement the high resolution data. 2D LASNEX modeling of the laser target conditions indicate that the high K-shell charge states are produced in the hot dense region of the plasma with electron temperature > keV and density approximately 1022 cm-3. These experiments demonstrate that with modest laser energy, plasmas heated by high-intensity 120 ps lasers provide a very bright source of hard approximately 8 keV x-ray emission.
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