Experiences with bubble detectors in monitoring neutron emission from spent reactor fuel

Bubble damage detectors were investigated as a possible nondestructive tool via neutron detection for in-field safeguards verification of spent fuel. Preliminary analysis of the influence of high gamma intensity and gamma energies above the deuteron disintegration threshold - required by this field of application - was performed under laboratory conditions. The effect of radiation damage on the neutron response proved to be negligible below 5 kGy gamma dose. Field tests were performed on spent fuel assemblies of a WWR-SM research reactor and a WWER-440 type power station. The results seem promising but the routine use of this novel method needs some further development work. (author)