The xhyphen;ray emission from a 375hyphen;kJ plasma focus is reported as measured on a timehyphen;resolved basis with Ross filters and silicon diode detectors. Thickhyphen;target electron beam spectra are calculated with a Monte Carlo electron beam transport program and fit to the experimental timehyphen;integrated xhyphen;ray spectra. A good fit is obtained with a 2hyphen;MAEminus;2power law electron beam, with cutoff energies at 8 and 200 keV, incident normal to a thick tungsten target. The source of the beam is judged to be electrons which are accelerated under the influence of strong electric fields. A 20hyphen;nsecQhyphen;switched ruby laser pulse injected tungsten ions via laser ablation prior to the initial dense pinch, and the xhyphen;ray emission below 4 keV was enhanced and that above 10 keV was reduced. The enhanced lowhyphen;energy xhyphen;ray emission is in agreement with calculated radiation for collisionalMhyphen;shell excitation of highly stripped tungsten in a 1.5hyphen;keV thermal plasma. A 900hyphen; mgr;sec ruby laser pulse injected sufficient tungsten ions to degrade greatly the initial dense plasma pinch and reduce the beam target xhyphen;ray emission. The timehyphen;resolved xhyphen;ray emission from this configuration appeared as a smooth Gaussian function in time with FWHMsim;200 nsec.
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