Photoexcitation of the isomers of 19 nuclides was examined in this work. Four accelerators were used as sources of bremsstrahlung to expose the samples and end-point energies covered the range from 0.5 to 11 MeV. No evidence was found for nonresonant processes of excitation. However, more than half the cases showed enhanced channels for the resonant photoexcitation of isomers with integrated cross sections approaching 10 ' cm keV. These results are three to four orders of magnitude larger than values usually characterizing {y, y') reactions.

The radiation responses of 4007's from a specific manufacturer with different packaging (i.e., plastic or ceramic) and/or electrical characterization (i.e., high-reliability or JAN) were found to vary significantly. Maintaining bias following irradiation was determined to be important in characterizing the anneal of both Al-and Si-gate inverters.Finally, dose-enhancement effects on the threshold-voltage shift were observed for 60Co inpool irradiations where the source and sample were separated by 20 in. of water.

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Proton beams with currents ⩾50 kA at 5 MeV in a ≲160-ns FWHM pulse have been extracted from an ion diode operated on the Aurora pulser. This current corresponds to an efficiency (proton currrent/total current) of 20%, which compares favorably with numerical simulation. The simulation indicates that the ion current is enhanced over the Child-Langmuir value due to increased electron lifetime in the diode. The proton beam directed onto a LiCl target provides a source of 1.8×1012 neutrons/sr/pulse in the forward direction from the 7Li(p,n) 7Be reaction.