An Empirical Measurement of the Specific (240)Pu Effective Mass of (238)Pu and (242)Pu
Specific (240) Pu-effective masses of (238)Pu and (242)Pu as required for the quantitative plutonium assay by passive neutron coincidence counting were determined experimentally with best possible accuracy. Three (238)PuO(2) samples, two (240)PuO(2) and two (242)PuO(2) samples, all in the approximate mass range 25-500mg, and prepared in standard type X.2 capsules at Harwell (UK), have been counted in two efficiency neutron coincidence counting chambers: the standard Euratom OSL-Chamber as utilized in the Euratom on-site laboratories and the Harwell Instruments N95 High Efficiency Neutron Coincidence Counter. Measured coincidence count rates were fully corrected for dead time, background and neutron multiplication effects. The present paper describes the experimental details and the evaluation of the (240)Pu-effective responses as determined for the given counters at standard gate width settings of the associated shift register electronics.
Bibliographic Reference: Paper presented: ESARDA 99, Seville (ES), 4-6th May (1999)
Availability: Available free of charge from CCR Ispra (IT)
Record Number: 199911349 / Last updated on: 1999-09-10
Original language: en
Available languages: en