Method for determining the quantity of plutonium in the presence of curium by passive neutron measurement

A nonlinear regression model using PVT plastic scintillators and tailored time windows effectively distinguishes plutonium from curium in neutron measurement, addressing overestimation issues and enhancing accuracy in passive neutron measurement systems.

FR3163462B1Active Publication Date: 2026-06-26COMMISSARIAT A LENERGIE ATOMIQUE ET AUX ENERGIES ALTERNATIVES
0 Cites 0 Cited by

Patent Information

Application Number
FR2024006476
Authority / Receiving Office
FR · FR
Patent Type
Patents
Current Assignee / Owner
Filing Date
2024-06-18
Publication Date
2026-06-26
Estimated Expiration
2044-06-18

AI Technical Summary

Technical Problem

Existing passive neutron measurement methods struggle to accurately determine the quantity of plutonium in the presence of curium in radioactive waste or nuclear materials, leading to significant overestimation due to curium's intense neutron emission, which masks the plutonium signal, especially when the mass ratio of curium to plutonium exceeds 0.1%, and are hindered by matrix effects and spurious gamma contributions.

Method used

A method utilizing a nonlinear regression model that analyzes pulse coincidences in distinct time intervals to differentiate plutonium and curium signals, employing polyvinyl-toluene (PVT) plastic scintillators to detect fast neutrons, and accounting for different neutron emission probabilities of 240Pu and 244Cm, with time windows selected to enhance discrimination.

Benefits of technology

The method provides precise estimation of plutonium mass even in the presence of curium, reducing overestimation errors and improving accuracy by exploiting the distinct neutron emission patterns of 240Pu and 244Cm, particularly when the mass ratio exceeds 0.1%, and mitigates spurious gamma contributions.

✦ Generated by Eureka AI based on patent content.
Patent Text Reader

Abstract

A method for determining the quantity of plutonium in a radioactive sample in the presence of curium, comprising the steps of: Measuring (301) a train of electrical pulses using a radiation detection system, Determining (302), respectively in a first and a second time window, a first and a second number of second-order pulse coincidences between the electrical pulses supplied by the detectors, The second time window being formed by the union of the first time window and a third time window, The first and third time windows being chosen such that the number of second-order pulse coincidences related to plutonium is greater than that related to curium in one of the two windows between the first and third time windows and less than that related to curium in the other window,Determine (304) the quantity of plutonium by applying a nonlinear regression model taking as parameters: the total number of measured pulses, the first number of second-order pulse coincidences, and the second number of second-order pulse coincidences, the model having been previously trained on a set of values ​​simulated from a numerical model. Figure 3,
Need to check novelty before this filing date? Find Prior Art