DETERMINATION OF RADIOACTIVITY BASED ON UNFOLDED GAMMA SPECTRA USING THE GRAVEL METHOD AND RESPONSE MATRIX FROM MCNP SIMULATION
Main Article Content
Abstract
This study presents an improved method for gamma-spectrometry analysis, particularly in low-energy regions, by combining the GRAVEL unfolding algorithm with a high-fidelity detector response matrix simulated using the MCNP6 code. The response matrix was constructed for a p-type HPGe detector up to 1 MeV. The method underwent a rigorous validation process using both synthetic spectra and a certified multi-nuclide point source, providing a strong foundation for its reliability. The results demonstrate a significant enhancement in peak separation and activity quantification, with relative deviations from certified activities reduced from as high as 47.8% (direct analysis) to below 4.3% after unfolding. This approach proves highly effective for accurately measuring low-energy and weak gamma emitters.
Keywords
Gamma Spectrometry, MCNP, Unfolding, FEP efficiency, Radioactivity
Article Details
References
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