A full spectral analysis method for the gamma spectrum: weighted library least squares

Area of Science:

• Nuclear Chemistry
• Spectroscopy
• Data Analysis

Background:

• Traditional library least squares (LLS) analysis in gamma spectroscopy is limited by inconsistent statistical uncertainties across different spectral channels.
• These inconsistencies lead to significant fluctuations and reduced reliability in analysis outcomes.

Purpose of the Study:

• To develop and validate a weighted library least squares (WLLS) approach to mitigate the effects of statistical uncertainty in gamma spectrum analysis.
• To enhance the precision and stability of results obtained from Prompt Gamma Neutron Activation Analysis (PGNAA).

Main Methods:

• A novel weighted library least squares (WLLS) method was developed, incorporating the square root of the count as a weighting factor in the regression objective function.
• A verification experiment was conducted using Prompt Gamma Neutron Activation Analysis (PGNAA) to evaluate the performance of the WLLS approach against the traditional LLS method.

Main Results:

• The WLLS approach successfully reduced the fluctuation level of statistical uncertainty in the gamma spectrum from 44.34 to 2.25.
• Analysis using WLLS demonstrated a significant reduction in the average standard deviation of results, achieving at least 0.37 times that of the LLS approach.

Conclusions:

• The proposed WLLS method effectively addresses the limitations of traditional LLS by accounting for statistical uncertainties in gamma spectral data.
• WLLS offers a more robust and accurate method for spectral analysis, particularly in applications like PGNAA, leading to improved data reliability and reduced result variability.