Algorithm development for low level radioxenon 2D spectra analysis: A first case of study using spectral unmixing for...

Area of Science:

• Nuclear physics and instrumentation
• Treaty verification technologies

Background:

• The Comprehensive nuclear Test Ban Treaty (CTBT) verification regime requires sensitive detection systems.
• Existing beta-gamma (β-γ) measurement analysis methods face challenges at low radiation statistics.

Purpose of the Study:

• To evaluate a new multiplicative spectral unmixing algorithm for full-spectrum analysis.
• To improve the accuracy of β-γ activity reconstruction and detection limits in low-statistics scenarios.

Main Methods:

• Development of new β-γ measurement systems by CEA/DAM.
• Testing a novel multiplicative spectral unmixing algorithm on simulated spectra from various mixtures.
• Comparison of the algorithm's performance against the classic region-of-interest (ROI) analysis method.

Main Results:

• The new algorithm demonstrated improved reconstruction of activities from simulated low-statistics spectra.
• Characteristic detection limits were found to be more favorable with the spectral unmixing approach.
• The algorithm shows potential for enhancing analysis at the limits of detection.

Conclusions:

• The multiplicative spectral unmixing algorithm offers a significant advancement for β-γ spectroscopy analysis.
• This method is particularly beneficial for CTBT verification applications dealing with low-level radioactive detections.
• The findings support the adoption of advanced spectral analysis techniques for improved treaty monitoring.